Successful surgical treatment of chronic ischemic mitral regurgitation achieves left ventricular reverse remodeling but does not affect right ventricular function

Right Ventricular Function in Surgical Treatment of Left Heart

Aim    The aim of this study was to evaluate right ventricular (RV) function during left chamber surgery.Material and methods    This was a single-site prospective cohort study. The study included 197 patients with valvular pathology of heart left chambers. Mean age of patients was 58 [47; 65] years. Precordial echocardiography was performed preoperatively and within one week after surgery.Results    Decreased parameters of the right ventricular (RV) longitudinal function and global contractile function were observed postoperatively in the majority of patients. More noticeable decreases were observed in parameters of the longitudinal function (p<0.001). Analysis of the changes in RV contractility depending on the underlying pathology revealed the greatest changes in the contractile function in the mitral insufficiency group. In the mitral stenosis group, the greatest difference was observed in the tricuspid annular systolic excursion (TAPSE) (p=0.027). In the groups with aortic defects, all parameters of RV contractile function, except for the fractional area change (FAC), showed statistically significant decreases after correction of the underlying defect (p<0.05).Conclusions    Surgical intervention for left heart valvulopathy can result in a decrease in RV function unrelated with systolic deficit of the left ventricle. Modern technologies allow multi-vector assessment of the RV contractile function. To assess the RV function, it is advisable to use a combination of parameters that reflect both global and longitudinal function.

Functional Tricuspid Regurgitation in Patients With Chronic Mitral Regurgitation: An Evidence-Based Narrative Review

Chronic mitral regurgitation leads to a series of downstream pathologic changes, including pulmonary hypertension, right ventricular dilation, tricuspid leaflet tethering, and tricuspid annular dilation, which can result in functional tricuspid regurgitation (FTR). The five-year survival rate for patients with severe FTR is reported to be as low as 34%. While FTR was often left uncorrected during left-heart valvular surgery, under the assumption that correction of the left-sided lesion would reverse the right-heart changes that cause FTR, recent data largely have supported concomitant tricuspid valve repair at the time of mitral surgery. In this review, the authors discuss the potentially irreversible nature of the changes leading to FTR, the likelihood of progression of FTR after mitral surgery, and the evidence for and against concomitant tricuspid valve repair at the time of mitral valve intervention. Lastly, this narrative review also examines advances in transcatheter therapies for the tricuspid valve and the evidence behind concomitant transcatheter tricuspid repair at the time of transcatheter mitral repair.

Right versus left heart reverse remodelling after treating ischaemic mitral and tricuspid regurgitation

OBJECTIVES

Repair outcomes of tricuspid regurgitation (TR) associated with ischaemic mitral regurgitation (IMR) are inferior to functional TR in terms of TR recurrence and right ventricular (RV) reverse remodelling. Our objective is to analyse right versus left heart reverse remodelling after surgery for IMR-associated TR.

METHODS

From 2001 to 2011, 568 patients with severe IMR underwent mitral valve surgery (repair 87%, replacement 13%), and 131 had concomitant tricuspid valve repair. Median follow-up was 3.0 years; 25% of living patients were followed up for 6.3 years. Longitudinal analysis of 1527 follow-up echocardiograms was performed to assess ventricular reverse remodelling and function.

RESULTS

Unlike the left heart, the right heart failed to reverse remodel (failed to recover ventricular function or halt dilatation). During follow-up after surgery, the right ventricle continued to dilate while the left ventricle regressed in size. RV ejection fraction decreased (46% at 1 month and 44% at 5 years), while left ventricular ejection fraction increased (33% and 37%, respectively). RV strain showed early (-11% at 1 month) and late (-12% at 5 years) dysfunction. Patients who underwent tricuspid valve repair had worse RV function. Mitral regurgitation remained stable after surgical intervention, and TR gradually recurred (37% moderate, 20% severe at 7 years).

CONCLUSIONS

Surgical treatment of IMR and TR along with revascularization failed to induce reverse remodelling of the right heart. These findings warrant further investigations to identify optimal timing and approach of intervention for IMR-associated TR with respect to RV remodelling.

Impact of recurrent mitral regurgitation after mitral valve repair for functional mitral regurgitation: long-term analysis of competing outcomes

AIMS

Recurrent mitral regurgitation (MR) has been reported after mitral valve repair for functional MR. However, the impact of recurrent MR on long-term survival remains poorly defined. In the present study, mortality-adjusted recurrent MR rates, the clinical impact of recurrent MR and its determinants were studied in patients after mitral valve repair with revascularization for functional MR in the setting of ischaemic heart disease.

METHODS AND RESULTS

Long-term clinical and echocardiographic outcome was evaluated in 261 consecutive patients after restrictive mitral annuloplasty and revascularization for moderate to severe functional MR, between 2000 and 2014. The cumulative incidence of recurrent MR ≥ Grade 2, assessed by competing risk analysis, was 9.6 ± 1.8% at 1-year, 20.3 ± 2.5% at 5-year, and 27.6 ± 2.9% at 10-year follow-up. Cumulative survival was 85.8% [95% confidence interval (CI) 81.0-90.0] at 1-year, 67.3% (95% CI 61.1-72.6%) at 5-year, and 46.1% (95% CI 39.4-52.6%) at 10-year follow-up. Age, preoperative New York Heart Association Class III or IV, a history of renal failure, and recurrence of MR expressed as a time-dependent variable [HR 3.28 (1.87-5.75), P < 0.001], were independently associated with an increased mortality risk. Female gender, a history of ST-elevation myocardial infarction, a preoperative QRS duration ≥120 ms, a higher preoperative MR grade, and a higher indexed left ventricular end-systolic volume were independently associated with an increased likelihood of recurrent MR.

CONCLUSION

Mitral valve repair for functional ischaemic MR resulted in a low incidence of recurrent MR with favourable clinical outcome up to 10 years after surgery. Presence of recurrent MR at any moment after surgery proved to be independently associated with an increased risk for mortality.

Current transcatheter devices to treat functional tricuspid regurgitation with discussion of issues relevant to clinical trial design

Functional or secondary tricuspid regurgitation (TR) has seen increased attention in recent times as relationships with clinically-relevant outcomes have come to light. Despite the association of increased mortality with significant TR, the disease remains under-recognized and thus relatively untreated. In addition, the disease itself has not been extensively studied and the interactions between annular dilatation, right heart disease and pulmonary hypertension are poorly understood. However, the high mortality and recurrence rate with current surgical replacement or repair techniques is well recognised, opening the door to transcatheter therapies for functional TR. The current perspective reviews the rationale for transcatheter solutions, describes some of the current approaches and discusses the ongoing questions of a poorly-studied condition which may limit the design of clinical trials for this disease.

Impact and evolution of right ventricular dysfunction after successful MitraClip implantation in patients with functional mitral regurgitation

BACKGROUND

Right ventricular dysfunction (RVdysf) is a predictor of poor outcome in patients with heart failure and valvular disease. The aim of this study was to evaluate the evolution and the impact of RVdysf in patients with moderate-severe functional mitral regurgitation (FMR) successfully treated with MitraClip.

METHODS AND RESULTS

From October 2008 to July 2014, 60 consecutive high surgical risk FMR patients were evaluated and stratified into two groups: RVdysf group (TAPSE < 16 mm and/or S'TDI < 10 cm/s, 21 patients) and No-RVdysf group (38 patients). The overall mean age of patients was 73 ± 8 (83% male). Ischemic FMR etiology was present in 67%. Mean LVEF was 30 ± 10%. Overall mean time follow-up was 565 ± 310 days. The only significant difference between the two groups was a greater prevalence of stroke, ICD and use of aldosterone antagonist in RVdysf group. Acute procedural success was achieved in 90% of patients. At 6-month echo-matched analysis significant RV function improvement was observed in patients with baseline RVdysf (TAPSE 15 ± 3.0 vs. 19 ± 4.5, p = 0.007; S'TDI 7 ± 1.2 vs. 11 ± 2.8, p < 0.0001; baseline vs. 6-month, respectively). The mean improvement in the 6-min walking test was significant in both groups (120 and 143 m, RVdysf and No-RVdysf groups, respectively). At Kaplan-Meier analysis, the presence of RVdysf did not affect the outcome in terms of freedom from composite efficacy endpoint.

CONCLUSIONS

This study shows that successful MitraClip implantation in patients with FMR and concomitant right ventricular dysfunction yields significant improvement of RV function at mid-term follow-up. Further data on larger population will be required to confirm our observations.

The Role of Right Ventricular Function in Mitral Valve Surgery

<p><b>Background:</b> An impaired right ventricular function is associated with a poor survival rate in patients with heart failure. Few investigations have analyzed the prognostic value of right ventricular function on the outcomes of mitral valve (MV) surgery. The objectives of this study were to define the effect of right ventricular function on postoperative outcomes after MV repair (MVP) or replacement (MVR).</p><p><b>Methods:</b> From September 2007 to February 2012, 335 consecutive patients underwent MVP or MVR at our institution. Preoperative transthoracic and transesophageal echocardiography (TEE) and postoperative TEE were used to define right ventricular function and MV performance. Preoperative right ventricular function was graded as normal to mild (grade 1-2) or as moderate to severe (grade 3-4). MV or tricuspid valve regurgitation was graded as non-trivial to mild (grade 0-2) or as moderate to severe (grade 3-4) preoperatively and postoperatively. Survival rate was evaluated at 1 year after surgery.</p><p><b>Results:</b> Of the 334 patients in the study, 280 patients showed a normal to a mildly impaired right ventricular function preoperatively (group 1). Fifty-four patients presented with moderate to severe right ventricular dysfunction (group 2). Patients with a compromised right ventricular function were more likely to undergo MVR (28.6% versus 53.7%, <i>P</i> <.001). The mean pulmonary artery pressure was 23.6 mm Hg in group 1 and 34 mm Hg in group 2 (<i>P</i> <.001). The left atrial diameter was 4.6 cm in group 1 and 5.3 cm in group 2 (<i>P</i> <.001). The 2 groups were not different with respect to operative mortality, but the patients in group 2 experienced more transfusion of blood products (588.4 mL versus 1180.6 mL, <i>P</i> <.001), longer intensive care unit stays (83.9 versus 149.6 hours, <i>P</i> <.001), and hospital stays (8.9 versus 12.8 days, <i>P</i> = .005). The rate of postoperative MV regurgitation was significantly higher in group 2 (1.8 versus 14.8%, <i>P</i> <.001). The overall 1-year survival rate was 92.5% in group 1 and 94.5% in group 2 (<i>P</i> = .59).</p><p><b>Conclusions:</b> This study has shown that a dysfunctional preoperative right ventricular function uses more resources and is associated with postoperative MV regurgitation, but it is not associated short- and mid-term mortality after MV surgery.</p>

Pseudoprolapse of the anterior leaflet in chronic ischemic mitral regurgitation: identification and repair

OBJECTIVE

Recurrence rates as high as 30% have been observed 6 months after treatment of chronic ischemic mitral regurgitation (CIMR) with isolated annuloplasty. We postulated that the high early recurrence rates resulted from the presence of untreated pseudoprolapse of the anterior leaflet.

METHODS

We conducted a retrospective study of all mitral valve repairs for CIMR performed by a single surgeon (S.W.H.) from 1995 to 2011. After annuloplasty, Gore-Tex neochordae were added if the high-pressure saline test indicated the presence of pseudoprolapse of the anterior leaflet.

RESULTS

A total of 47 patients underwent mitral valve repair for CIMR. Of the 47 patients, 24 (51%) were found to have pseudoprolapse requiring the addition of neochordae. For all patients, the average age was 65.1 years, and 65.2% were men. Fourteen (30%) had had a preoperative intra-aortic balloon pump placed by cardiologists. Fourteen (30%) had severe pulmonary hypertension. Concomitant coronary artery bypass grafting was performed in 40 patients, with an average of 2.2 grafts; 7 had previously undergone coronary artery bypass grafting. Mitral Carpentier-Edwards physio annuloplasty rings were used in all patients with a mean size of 29 mm. One patient died postoperatively. Follow-up data were available for all 47 patients at an average of 4.9 years. The 5-year survival rate was 82.5%. The mean pre- and postoperative New York Heart Association class, ejection fraction, and mitral regurgitation grade were 3 and 1.52 (P < .0001), 34% and 41% (P = .0006), and 3.51 and 1.08 (P < .0001), respectively. Two patients developed greater than moderate mitral regurgitation.

CONCLUSIONS

Effective repair of CIMR should include surgical techniques to correct pseudoprolapse of the anterior leaflet, when present. The selective addition of Gore-Tex neochordae to an undersized annuloplasty nearly eliminates recurrent regurgitation after mitral valve repair for CIMR.