Abstract

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BACKGROUND:

Mitral-valve repair can be accomplished with an investigational procedure that involves the percutaneous implantation of a clip that grasps and approximates the edges of the mitral leaflets at the origin of the regurgitant jet.

METHODS:

We randomly assigned 279 patients with moderately severe or severe (grade 3+ or 4+) mitral regurgitation in a 2:1 ratio to undergo either percutaneous repair or conventional surgery for repair or replacement of the mitral valve. The primary composite end point for efficacy was freedom from death, from surgery for mitral-valve dysfunction, and from grade 3+ or 4+ mitral regurgitation at 12 months. The primary safety end point was a composite of major adverse events within 30 days.

RESULTS:

At 12 months, the rates of the primary end point for efficacy were 55% in the percutaneous-repair group and 73% in the surgery group (P=0.007). The respective rates of the components of the primary end point were as follows: death, 6% in each group; surgery for mitral-valve dysfunction, 20% versus 2%; and grade 3+ or 4+ mitral regurgitation, 21% versus 20%. Major adverse events occurred in 15% of patients in the percutaneous-repair group and 48% of patients in the surgery group at 30 days (P<0.001). At 12 months, both groups had improved left ventricular size, New York Heart Association functional class, and quality-of-life measures, as compared with baseline.

CONCLUSIONS:

Although percutaneous repair was less effective at reducing mitral regurgitation than conventional surgery, the procedure was associated with superior safety and similar improvements in clinical outcomes. (Funded by Abbott Vascular; EVEREST II ClinicalTrials.gov number, NCT00209274.).

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Abstract

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The aim of the study was to evaluate the additional diagnostic value of real-time 3-dimensional transesophageal echocardiography (RT3D-TEE) for surgically recognized mitral valve (MV) prolapse anatomy compared to 2-dimensional transthoracic echocardiography (2D-TTE), 2D-transesophageal echocardiography (2D-TEE), and real-time 3D-transthoracic echocardiography (RT3D-TTE). We preoperatively analyzed 222 consecutive patients undergoing repair for prolapse-related mitral regurgitation using RT3D-TEE, 2D-TEE, RT3D-TTE, and 2D-TTE. Multiplanar reconstruction was added to volume-rendered RT3D-TEE for quantitative prolapse recognition. The echocardiographic data were compared to the surgical findings. Per-patient analysis of RT3D-TEE identified prolapse in 204 patients more accurately (92%) than 2D-TEE (78%), RT3D-TTE (80%), and 2D-TTE (54%). Even among those 60 patients with complex prolapse (>1 segment localization or commissural lesions), RT3D-TEE correctly identified 58 (96.5%) compared to 42 (70%), 31 (52%), and 21 (35%) detected by 2D-TEE, RT3D-TTE, and 2D-TTE (p < 0.0001). Multiplanar reconstruction enabled RT3D-TEE to differentiate dominant (=5-mm displacement) and secondary (2 to <5-mm displacement) prolapsed segments in agreement with surgically recognized dominant lesions (100%), but with a low predictive value (34%) for secondary lesions. In addition, owing to the identification of clefts and subclefts (indentations of MV tissue that extended =50% or <50% of the total leaflet height, respectively), RT3D-TEE accurately characterized the MV anatomy, including that which deviated from the standard nomenclature. In conclusion, RT3D-TEE provided more accurate mapping of MV prolapse than 2D imaging and RT3D-TTE, adding quantitative recognition of dominant and secondary lesions and MV anatomy details.

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Abstract

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AIMS:

To determine the frequency, predictors, and outcome implications of pulmonary hypertension (PH) diagnosed by Doppler echocardiography in a large cohort of patients with the homogenous diagnosis of degenerative mitral regurgitation (MR) due to flail leaflets.

METHODS AND RESULTS:

The Mitral Regurgitation International DAtabase (MIDA) is a registry including patients with MR due to flail leaflets consecutively referred at tertiary centres in Europe and the USA. Between 1987 and 2004, pulmonary artery systolic pressure (PASP) was measured at baseline by Doppler echocardiography in 437 patients (age 67 ± 11 years; 66% men). Pulmonary hypertension (PASP > 50 mmHg) was observed in 102 patients (23%). Independent predictors of PH were age and left atrial size (P < 0.0001). During a mean follow-up of 4.8 ± 2.8 years, PH was a strong independent predictor of death [adjusted HR 2.03 (1.30-3.18) P = 0.002], cardiovascular death [CVD; adjusted HR 2.21 (1.30-3.76) P = 0.003], and heart failure [adjusted HR 1.70 (1.10-2.62) P = 0.018]. Mitral valve surgery at any time during follow-up (performed in 325 patients, 75%) was beneficial [adjusted HR for death 0.22 (0.14-0.36) P < 0.001], but PH was associated with the increased risk of postoperative death and CVD (P = 0.01).

CONCLUSION:

Pulmonary hypertension is a frequent complication of significant MR due to flail leaflet and is associated with major outcome implications, approximately doubling the risk of death and heart failure after diagnosis. Mitral valve surgery performed during follow-up is beneficial but does not completely abolish the adverse effects of PH once it is established and is particularly beneficial in patients without PH. These data support relieving PH secondary to MR due to flail leaflet, but also careful consideration for mitral surgery before PH is established.

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Abstract

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BACKGROUND:

Whether morphological abnormalities of the mitral valve represent part of the hypertrophic cardiomyopathy (HCM) disease process is unresolved. Therefore, we applied cardiovascular magnetic resonance to characterize mitral valve morphology in a large HCM cohort.

METHODS AND RESULTS:

Cine cardiac magnetic resonance images were obtained in 172 HCM patients (age, 42±18 years; 62% men) and 172 control subjects. In addition, 15 HCM gene-positive/phenotype-negative relatives were studied. Anterior mitral leaflet (AML) and posterior mitral leaflet lengths were greater in HCM patients than in control subjects (26±5 versus 19±5 mm, P<0.001; and 14±4 versus 10±3 mm, P<0.001, respectively), including 59 patients (34%) in whom AML length alone, posterior mitral leaflet length alone, or both were particularly substantial (>2 SDs above controls). Leaflet length was increased compared with controls in virtually all HCM age groups, including young patients 15 to 20 years of age (AML, 26±5 versus 21±4 mm; P=0.0002) and those =60 years of age (AML, 26±4 versus 19±2 mm; P<0.001). No relation was evident between mitral leaflet length and LV thickness or mass index (P=0.09 and P=0.16, respectively). A ratio of AML length to LV outflow tract diameter of >2.0 was associated with subaortic obstruction (P=0.001). In addition, AML length in 15 genotype-positive relatives without LV hypertrophy exceeded that of matched control subjects (21±3 versus 18±3 mm; P<0.01).

CONCLUSIONS:

In HCM, mitral valve leaflets are elongated independently of other disease variables, likely constituting a primary phenotypic expression of this heterogeneous disease, and are an important morphological abnormality responsible for LV outflow obstruction in combination with small outflow tract dimension. These findings suggest a novel role for cardiac magnetic resonance in the assessment of HCM.

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Abstract

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BACKGROUND:

Optimal timing of surgery in degenerative mitral regurgitation (MR) remains a controversial topic. The impact of current ACC/AHA guideline recommendations about optimal timing of surgery on outcomes is untested and contemporary data are lacking.

OBJECTIVE: To assess the association between the timing of surgery and long-term survival in patients with severe MR.

METHODS:

A cohort of 481 patients with severe, degenerative mitral regurgitation (1995-2007) from the Duke Cardiovascular Disease Databank who fulfilled at least one ACC/AHA guideline indication for surgery was identified. Exclusion criteria were rheumatic disease, congenital mitral valve (MV) disease, hypertrophic cardiomyopathy, coronary disease in more than one vessel, endocarditis, other severe valve disease, h/o valve repair/replacement. Patients were grouped into early surgery (in = 2 months of presenting with surgical indications) and late surgery (>2 months) groups. An adjusted Cox regression model was constructed for time to death after 2 months with a time-dependent covariate term for late surgery.

RESULTS:

168 patients had early surgery (median time to surgery 0.42 months) with 153 followed up after 2 months, 94 had late surgery (median time to surgery 8.75 months) and 219 medically managed. 127/168 in the early surgery group and 84/94 in the late surgery group received MV repair (p=0.02). Over 5.6 years' (median) follow-up there were 35 deaths (21%) in the early surgery group, with two occurring before 2 months and 20 (21%) in the late group. In the multivariable model, those undergoing early surgery had a lower hazard for death than those who underwent late surgery (HR=0.54 (95% CI 0.30 to 0.97), p=0.039). MV repair was independently associated with survival (HR=0.45 (95% CI 0.25 to 0.83), p=0.01).

CONCLUSIONS:

In patients with severe MR who presented with guideline indications for surgery, those selected for earlier surgery had improved survival. These data support the current guidelines for early referral to surgery in patients with severe MR for enlarged left ventricular dimensions, reduced ejection fraction and symptoms rather than delaying surgery. Larger randomised trials are needed to definitively answer the question of optimal timing of surgery in patients with severe degenerative MR.

 

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Abstract

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Pulmonary hypertension represents an important cause of morbidity and mortality in patients with mitral stenosis who undergo cardiac surgery, especially in the postoperative period. The aim of this study was to test the hypothesis that inhaled nitric oxide (iNO) would improve the hemodynamic effects and short-term clinical outcomes of patients with mitral stenosis and severe pulmonary hypertension who undergo cardiac surgery in a randomized, controlled study. Twenty-nine patients (4 men, 25 women; mean age 46 ± 2 years) were randomly allocated to receive iNO (n = 14) or oxygen (n = 15) for 48 hours immediately after surgery. Hemodynamic data, the use of vasoactive drugs, duration of stay, and short-term complications were assessed. No differences in baseline characteristics were observed between the groups. After 24 and 48 hours, patients receiving iNO had a significantly greater increase in cardiac index compared to patients receiving oxygen (p <0.0001). Pulmonary vascular resistance was also more significantly reduced in patients receiving iNO versus oxygen (-117 dyne/s/cm(5), 95% confidence interval -34 to -200, vs 40 dyne/s/cm(5), 95% confidence interval -34 to 100, p = 0.005) at 48 hours. Patients in the iNO group used fewer systemic vasoactive drugs (mean 2.1 ± 0.14 vs 2.6 ± 0.16, p = 0.046) and had a shorter intensive care unit stay (median 2 days, interquartile range 0.25, vs median 3 days, interquartile range 7, p = 0.02). In conclusion, iNO immediately after surgery in patients with mitral stenosis and severe pulmonary hypertension improves hemodynamics and may have short-term clinical benefits.

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Abstract

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OBJECTIVE:

Recent reports have shown that robotic mitral valve repair is effective in treating posterior leaflet disease; however, comparison with trans-sternal (open) valvuloplasty for all prolapse categories has not been performed. Moreover, data from the recently published EVEREST II trial infer that adverse event rates after mitral valve repair for degenerative disease are high. We therefore compared early outcomes of robotic versus open mitral valve repair for patients with mitral valve prolapse.

METHODS:

Among 745 consecutive patients undergoing open or robotic mitral repair for degenerative disease, 95 propensity-matched pairs were identified. Leaflet prolapse categories were similar between groups. Complete mitral valve repair was performed using identical techniques.

RESULTS:

Median crossclamp and bypass times were longer in the robotic group but decreased significantly over time (P < .001). There were no conversions to open sternotomy, repair rate and early survival were 100%, dismissal mitral regurgitation grade was similar (P = 1.00), and all patients in the robotic group had mild or less mitral regurgitation at 1 month after repair. There were no differences in adverse events (5% open vs 4% robotic, P = 1.00). Patients in the robotic group had shorter postoperative ventilation time, intensive care unit stay, and hospital stay.

CONCLUSIONS:

Robotic mitral valve repair allows complete anatomic correction of all categories of leaflet prolapse using techniques identical to open approaches. Robotic repair effectively corrects mitral regurgitation, offers excellent freedom from adverse events, and facilitates rapid weaning from ventilation, translating into earlier hospital dismissal. Safety and efficacy after both open and robotic mitral valve repair are higher than recently reported in the EVEREST II trial and establish a benchmark against which nonsurgical therapies should be evaluated.

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Abstract

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OBJECTIVE:

Less invasive approaches to mitral valve surgery are increasingly used for improved cosmesis; however, few studies have investigated their effect on outcome. We sought to compare these minimally invasive approaches fairly with conventional full sternotomy by using propensity-matching methods.

METHODS:

From January 1995 to January 2004, 2124 patients underwent isolated mitral valve surgery through a minimally invasive approach, and 1047 underwent isolated mitral valve surgery through a conventional sternotomy. Because there were important differences in patient characteristics, a propensity score based on 42 factors was used to obtain 590 well-matched patient pairs (56% of cases).

RESULTS:

In-hospital mortality was similar for propensity-matched patients: 0.17% (1/590) for those undergoing minimally invasive surgery and 0.85% (5/590) for those undergoing conventional surgery (P = .2). Occurrences of stroke (P = .8), renal failure (P > .9), myocardial infarction (P = .7), and infection (P = .8) were also similar. However, 24-hour mediastinal drainage was less after minimally invasive surgery (median, 250 vs 350 mL; P < .0001), and fewer patients received transfusions (30% vs 37%, P = .01). More patients undergoing minimally invasive surgery were extubated in the operating room (18% vs 5.7%, P < .0001), and postoperative forced expiratory volume in 1 second was higher. Early after operation, pain scores were lower (P < .0001) after minimally invasive surgery.

CONCLUSION:

Within that portion of the spectrum of mitral valve surgery in which propensity matching was possible, minimally invasive mitral valve surgery had cosmetic, blood product use, respiratory, and pain advantages over conventional surgery, and no apparent detriments. Mortality and morbidity for robotic and percutaneous procedures should be compared with these minimally invasive outcomes.

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Abstract

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OBJECTIVE:

To determine if the time required to perform mitral valve repairs using telemanipulation technology decreases with experience and how that decrease is influenced by patient and procedure variables.

METHODS:

A single-center retrospective review was conducted using perioperative and outcomes data collected contemporaneously on 458 mitral valve repair surgeries using telemanipulative technology. A regression model was constructed to assess learning with this technology and predict total robot time using multiple predictive variables. Statistical analysis was used to determine if models were significantly useful, to rule out correlation between predictor variables, and to identify terms that did not contribute to the prediction of total robot time.

RESULTS:

We found a statistically significant learning curve (P < .01). The institutional learning percentage* derived from total robot times† for the first 458 recorded cases of mitral valve repair using telemanipulative technology is 95% (R(2) = .40). More than one third of the variability in total robot time can be explained through our model using the following variables: type of repair (chordal procedures, ablations, and leaflet resections), band size, use of clips alone in band implantation, and the presence of a fellow at bedside (P < .01).

CONCLUSIONS:

Learning in mitral valve repair surgery using telemanipulative technology occurs at the East Carolina Heart Institute according to a logarithmic curve, with a learning percentage of 95%. From our regression output, we can make an approximate prediction of total robot time using an additive model. These metrics can be used by programs for benchmarking to manage the implementation of this new technology, as well as for capacity planning, scheduling, and capital budget analysis.

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Abstract

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AIMS:

Feasibility and efficacy of mitral repair in the elderly remain controversial. This study aims to compare outcomes of mitral repair and replacement in octogenarians.

METHODS AND RESULTS:

We compared the outcomes of 322 consecutive octogenarian patients (mean age 82.6 ± 2.2 years) who underwent mitral repair (n = 227, 70%) or replacement (n = 95, 30%) at Mount Sinai Medical Center and Leipzig Herzzentrum between 1998 and 2008 using propensity score adjustment and univariate and multivariate analyses. Patients undergoing aortic valve replacement were excluded. Coronary bypass was performed in 47.5% (n = 153), and 31.1% (n = 100) required tricuspid repair. Propensity score adjustment yielded comparable groups. Thirty-day mortality in patients undergoing primary elective mitral repair for degenerative disease was 5.1% (2/39). Overall 90-day mortality was 18.9% (43/227) for repair compared with 31.6% (30/95) for replacement (P = 0.014). Pre-discharge echocardiography revealed less than moderate residual regurgitation in 99% of patients (231/232). Adjusted 1-, 3-, and 5-year survival for patients undergoing mitral repair was 71 ± 3, 61 ± 4, and 59 ± 4%, respectively, compared with 56 ± 5, 50 ± 6, and 45 ± 6% for patients undergoing mitral replacement (P = 0.046). Multivariate analysis demonstrated emergency surgery, previous myocardial infarction, concomitant coronary artery bypass surgery, and mitral replacement to be strong independent predictors of early mortality; mitral valve replacement was an independent predictor of reduced survival in degenerative patients.

CONCLUSION:

Elective mitral repair can be performed with low operative mortality and good long-term outcomes in selected octogenarians with degenerative mitral disease, and is associated with better long-term survival than mitral replacement. The survival benefit associated with surgery for non-degenerative disease is more questionable.

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Abstract

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OBJECTIVE:

The study objective was to evaluate the long-term (5-year) safety and efficacy of mitral valve surgery with and without the CorCap cardiac support device (Acorn Cardiovascular, St Paul, Minn) in patients with dilated cardiomyopathy and New York Heart Association class II-IV heart failure.

BACKGROUND:

The Acorn trial provided a unique opportunity to assess the long-term safety and efficacy of mitral valve surgery because clinical visits and echocardiograms (read by a core laboratory) were completed for 5 years of follow-up. Further, this study provided follow-up data on the long-term effect of the CorCap cardiac support device as an adjunct to mitral valve surgery.

METHODS:

From the original Acorn trial (n = 300 patients), 193 patients were enrolled in the mitral valve repair/replacement stratum. A total of 102 were randomized to mitral valve surgery alone (control group) and 91 were randomized to mitral valve surgery with implantation of the CorCap cardiac support device (treatment group). Patients were followed up for 5 years.

RESULTS:

As previously reported, 30-day operative mortality was only 1.6%. At 5 years, the total mortality was 30% with an average annual mortality rate of approximately 6% per year. The effects of mitral valve surgery led to a progressive decrease in left ventricular end-diastolic and end-systolic volumes, which were highly significant at all time points. At the end of 5 years, there was an average reduction in left ventricular end-diastolic volume of 75 mL, which represents a 28% reduction from baseline. During 5 years of follow-up, 29 patients had recurrent mitral regurgitation and 5 patients underwent repeat mitral valve surgery. The addition of the CorCap device led to greater decreases in left ventricular end-diastolic volume (average difference of 16.5 mL; P = .05), indicating that the CorCap device had an additive effect to the mitral valve operation.

CONCLUSIONS:

This study demonstrates long-term improvement in left ventricular structure and function after mitral valve surgery for up to 5 years. These data provide evidence supporting mitral valve repair in combination with the Acorn CorCap device for patients with nonischemic heart failure with severe left ventricular dysfunction who have been medically optimized yet remain symptomatic with significant mitral regurgitation.

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Abstract

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OBJECTIVE:

Owing to the complexity of the underlying lesions, Barlow disease remains a challenge for surgeons performing mitral valve repair. We aimed to assess whether our most recent results involving several surgeons were comparable with those of a previous experience in which mitral valve repair was performed by a more limited group of surgeons.

METHODS:

From September 2000 to January 2007, 200 patients with Barlow disease (135 men and 65 women; mean age, 56 ± 13 years) were referred to our institution for surgical treatment of their mitral regurgitation. We retrospectively analysed the mitral lesions characteristics, the surgical techniques used, and clinical outcomes. Follow-up echocardiograms were biannually reviewed.

RESULTS:

Lesions comprised annular dilatation, excess tissue, and leaflet prolapse in all cases. The most frequent prolapsed segments were P2 (88.5%; n = 177) and A2 (55.5%; n = 111). Annular calcifications and restrictive valvular motion were associated in 20% (n = 40). Repair was feasible in 94.7% (n = 179/189) of non-redo interventions. Immediate postoperative echocardiography showed residual mitral regurgitation greater than 1+ in 6 cases; these patients were all reoperated on within the next months. Operative mortality was 1.5% (n = 3). Mean follow-up was 77.5 ± 25.6 months. At 8 years postoperatively, overall survival was 88.6% ± 3.1%, freedom from reintervention was 95.3% ± 1.7%, and freedom from late recurrent moderate mitral regurgitation (>2+) was 90.2% ± 3.1%

CONCLUSIONS:

Provided that the fundamental principles of mitral valve reconstruction are respected, the surgical techniques are highly reproducible with good long-term results, similar to those published during the pioneering phase of this surgery.

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Abstract

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There is uncertainty and debate regarding whether ischemic mitral regurgitation (MR) is a secondary epiphenomenon resulting from left ventricular (LV) dysfunction or confers an independent effect on exercise capacity and outcomes. We tested whether ischemic MR negatively affects exercise capacity and cardiovascular morbidity and mortality in patients with coronary artery disease (CAD) and those with inferior wall motion abnormality independent of LV dysfunction. Clinical follow-up over 5 years was obtained in 77 patients (64 ± 10 years old, LV ejection fraction 54 ± 11%) with at least mild ischemic MR from CAD and evidence of inferior wall motion abnormality who had exercise stress testing with perfusion imaging within 24 hours of echocardiography. Patients with active heart failure, ischemia, intrinsic valve disease, pulmonary and vascular diseases were excluded. Exercise capacity (METs, peak double product) was tested for relation to MR (vena contracta [VC] and jet area), LV size and function, and pulmonary pressures. Cox proportional hazards analysis assessed whether MR predicted cardiovascular events including hospitalization for heart failure, acute coronary syndrome, and myocardial infarction and cardiovascular and total mortalities. Univariate correlation identified MR with VC (r = -0.674, p <0.0001) and MR jet area (r = -0.575, p <0.0001) as determinants of decreased functional capacity evaluated by METs, with VC the stronger predictor. MR VC >2 mm (moderate ischemic MR) and age were independent predictors of cardiovascular events and death (hazard ratio 6.72 for MR, p = 0.04). In conclusion, in patients with CAD and LV inferior wall motion abnormality, MR negatively affects exercise capacity and is associated with increased cardiovascular morbidity and mortality. This effect appears independent of degree of LV dysfunction.

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Abstract

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BACKGROUND:

Functional mitral regurgitation (FMR) is a common finding in patients with heart failure (HF), but its effect on outcome is still uncertain, mainly because in previous studies sample sizes were relatively small and semiquantitative methods for FMR grading were used

OBJECTIVE:

To evaluate the prognostic value of FMR in patients with HF.

METHODS AND RESULTS:

Patients with HF due to ischaemic and non-ischaemic dilated cardiomyopathy (DCM) were retrospectively recruited. The clinical end point was a composite of all-cause mortality and hospitalisation for worsening HF. FMR was quantitatively determined by measuring vena contracta (VC) or effective regurgitant orifice (ERO) or regurgitant volume (RV). Severe FMR was defined as ERO >0.2 cm2 or RV >30 ml or VC >0.4 cm. Restrictive mitral filling pattern (RMP) was defined as E-wave deceleration time <140 ms. The study population comprised 1256 patients (mean age 67611; 78% male) with HF due to DCM: 27% had no FMR, 49% mild to moderate FMR and 24% severe FMR. There was a powerful association between severe FMR and prognosis (HR¼2.0, 95% CI 1.5 to 2.6; p<0.0001) after adjustment of left ventricular ejection fraction and RMP. The independent association of severe FMR with prognosis was confirmed in patients with ischaemic DCM (HR¼2.0, 95% CI 1.4 to 2.7; p<0.0001) and non-ischaemic DCM (HR¼1.9, 95% CI 1.3 to 2.9;p¼0.002).

CONCLUSION:

In a large patient population it was shown that a quantitatively defined FMR was strongly associated with the outcome of patients with HF, independently of LV function.

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Abstract

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BACKGROUND:

Functional mitral regurgitation (MR) is a common finding in heart failure patients with dilated cardiomyopathy and has important prognostic implications. However, the increased operative risk of these patients may result in low referral or high denial rate for mitral valve surgery. Cardiac resynchronization therapy (CRT) has been shown to have a favorable effect on MR. Aims of this study were to (1) evaluate CRT as a therapeutic option in heart failure patients with functional MR and high operative risk and (2) investigate the effect of MR improvement after CRT on prognosis.

METHODS AND RESULTS:

A total of 98 consecutive patients with moderate-severe functional MR and high operative risk underwent CRT according to current guidelines. Echocardiography was performed at baseline and 6-month follow-up; severity of MR was graded according to a multiparametric approach. Significant improvement of MR was defined as a reduction ≥1 grade. All-cause mortality was assessed during follow-up (median 32 [range 6.0 to 116] months). Thirteen patients (13%) died before 6-months follow-up. In the remaining 85 patients, significant reduction in MR was observed in all evaluated parameters. In particular, 42 patients (49%) improved ≥1 grade of MR and were considered MR improvers. Survival was superior in MR improvers compared to MR nonimprovers (log rank P<0.001). Mitral regurgitation improvement was an independent prognostic factor for survival (hazard ratio 0.35, confidence interval 0.13 to 0.94; P=0.043).

CONCLUSIONS:

Cardiac resynchronization therapy is a potential therapeutic option in heart failure patients with moderate-severe functional MR and high risk for surgery. Improvement in MR results in superior survival after CRT.

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Abstract

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AIMS:

To assess the feasibility, short-term durability and clinical outcomes of MitraClip® therapy for mitral regurgitation (MR) in patients with end-stage heart failure and a severely reduced left ventricular (LV) ejection fraction.

METHODS AND RESULTS:

We analysed retrospectively collected data from seven European centres. Included in the study were 50 heart failure patients [mean age 70 ± 11 years, 38 men (76%)] with a LV ejection fraction ≤25% and MR of at least grade 3+. All patients had functional MR, were in New York Heart Association (NYHA) functional class III or IV, and their mean logistic EuroSCORE was 34%. The patients underwent a total of 53 MitraClip® procedures; one or more clips were implanted in 50 procedures (48 patients), for an acute procedural success rate of 94%. Severity of MR was reduced in all successfully treated patients, 44 (92%) were discharged with MR ≤2+. Thirty-day mortality was 6%; cumulative survival at 6 months was 81.2%. Clinical and echocardiographic 6-month follow-up data were obtained from 32 and 31 successfully treated patients, respectively. At 6 months, MR ≤2+ was present in 27 (87%) of 31 patients, and 23 (72%) of 32 patients were in NYHA functional class I or II. Six-minute walk distance improved significantly, and significant reductions in LV volumes indicative of reverse LV remodelling were concordant with significant reductions in N-terminal pro-brain natriuretic peptide plasma levels.

CONCLUSION:

MitraClip® therapy reduces functional MR in patients with end-stage heart failure and marked LV dysfunction and entails clinical benefit at 6 months.

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Abstract

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BACKGROUND:

It remains controversial whether restrictive mitral annuloplasty (RMA) for functional mitral regurgitation (MR) can induce functional mitral stenosis (MS) that may cause postoperative residual pulmonary hypertension (PH).

METHODS AND RESULTS:

One hundred eight patients with left ventricular (LV) dysfunction and severe MR underwent RMA with stringent downsizing of the mitral annulus. Systolic pulmonary artery pressure (PAP) and mitral valve performance variables were determined by Doppler echocardiography prospectively and 1 month after RMA. Fifty-eight patients underwent postoperative hemodynamic measurements. Postoperative echocardiography showed a mean pressure half-time of 92 ± 14 ms, a transmitral mean gradient of 2.9 ± 1.1 mm Hg, and a mitral valve effective orifice area of 2.4 ± 0.4 cm(2), consistent with functional MS. Doppler-derived systolic PAP was 32 ± 8 mm Hg, which correlated weakly with the transmitral mean gradient (ρ=0.23, P=0.02). Postoperative cardiac catheterization also showed significant improvements in LV volume and systolic function, pulmonary capillary wedge pressure, cardiac index, and systolic PAP; the latter was associated with LV end-diastolic pressure [standardized partial regression coefficient (SPRC)=0.51], pulmonary vascular resistance (SPRC=0.47), cardiac index (SPRC=0.37), and transmitral pressure gradient (SPRC=0.20). In a multivariate Cox proportional hazard model, postoperative PH (systolic PAP >40 mm Hg), but not mitral valve performance variables, was strongly associated with adverse cardiac events.

CONCLUSIONS:

RMA for functional MR resulted in varying degrees of functional MS. However, our data were more consistent with the residual PH being caused by LV dysfunction and pulmonary vascular disease than by the functional MS. The residual PH, not functional MS, was the major predictor of post-RMA adverse cardiac events.

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