Ischaemic mitral regurgitation: pathophysiology, outcomes and the conundrum of treatment

Efficacy of early administration of sacubitril/valsartan after coronary artery revascularization in patients with acute myocardial infarction complicated by moderate-to-severe mitral regurgitation: a randomized controlled trial

Effects of angiotensin receptor/neprilysin inhibitors (ARNI) on ventricular remodeling in patients with heart failure, especially heart failure with reduced ejection fraction (HFrEF), are better than those of angiotensin-converting enzyme inhibitors (ACEI). Acute myocardial infarction (AMI) complicated by mitral regurgitation exacerbates ventricular remodeling and increases the risk of heart failure. There is limited evidence on the effects of early administration of ARNI in patients with AMI complicated by mitral regurgitation. The aim of this trial was to examine the effectiveness and the safety of early administration of sacubitril/valsartan after coronary artery revascularization in patients with AMI complicated by moderate-to-severe mitral regurgitation. This was a randomized, single-blind, parallel-group, controlled trial. From June 2021 to June 2022, we enrolled 142 consecutive patients with AMI complicated by moderate-to-severe mitral regurgitation and followed them for 12 months. The patients received standard treatment for AMI and were randomly assigned to receive ARNI or benazepril. The primary efficacy end points were the differences in mitral regurgitant jet area (MRJA), mitral regurgitant volume (MRV), concentration of n-terminal pro-brain natriuretic peptide (NT-proBNP), left ventricular ejection fraction (LVEF), and left ventricular end-diastolic volume and end-systolic volume (LVEDV and LVESV) between groups and within groups at baseline, 1, 3, 6, and 12 months. Secondary end points included the rates of heart failure hospitalization, all-cause mortality, refractory angina, malignant arrhythmias, recurrent myocardial infarction, and stroke. Safety end points included the rates of hyperkalemia, renal dysfunction, hypotension, angioedema, and cough. The ARNI group had significantly lower NT-proBNP levels than the benazepril group at 1 month and later (P < 0.001). MRJA and MRV significantly improved in the ARNI group compared with the benazepril group at 12 months (MRJA: - 3.21 ± 2.18 cm2 vs. - 1.83 ± 2.81 cm2, P < 0.05; MRV: - 27.22 ± 15.22 mL vs. - 13.67 ± 21.02 mL, P < 0.001). The ARNI group also showed significant reductions in LVEDV and LVESV (P < 0.05) and improvement in LVEF (P < 0.05). Secondary end point analysis showed a significantly higher rate of heart failure hospitalization in the benazepril group compared with the ARNI group (HR = 2.03, 95% CI 1.12-3.68, P = 0.021). Safety end point analysis showed a higher rate of hypotension in the ARNI group (P < 0.05). Early use of sacubitril/valsartan after coronary artery revascularization in patients with AMI complicated by moderate-to-severe mitral regurgitation can significantly reduce mitral regurgitation, improve ventricular remodeling, and decrease heart failure hospitalization. Nevertheless, caution is needed to avoid hypotension. Chinese Clinical Trial Registry (ChiCTR2100054255) registered on December 11, 2021.

Cardiac Computed Tomography of Native Cardiac Valves

Valvular heart disease (VHD) is a significant clinical problem associated with high morbidity and mortality. Although not being the primary imaging modality in VHD, cardiac computed tomography (CCT) provides relevant information about its morphology, function, severity grading, and adverse cardiac remodeling assessment. Aortic valve calcification quantification is necessary for grading severity in cases of low-flow/low-gradient aortic stenosis. Moreover, CCT details significant information necessary for adequate percutaneous treatment planning. CCT may help to detail the etiology of VHD as well as to depict other less frequent causes of valvular disease, such as infective endocarditis, valvular neoplasms, or other cardiac pseudomasses.

An Image-Based Computational Fluid Dynamics Study of Mitral Regurgitation in Presence of Prolapse

PURPOSE

In this work we performed an imaged-based computational study of the systolic fluid dynamics in presence of mitral valve regurgitation (MVR). In particular, we compared healthy and different regurgitant scenarios with the aim of quantifying different hemodynamic quantities.

METHODS

We performed computational fluid dynamic (CFD) simulations in the left ventricle, left atrium and aortic root, with a resistive immersed method, a turbulence model, and with imposed systolic wall motion reconstructed from Cine-MRI images, which allowed us to segment also the mitral valve. For the regurgitant scenarios we considered an increase of the heart rate and a dilation of the left ventricle.

RESULTS

Our results highlighted that MVR gave rise to regurgitant jets through the mitral orifice impinging against the atrial walls and scratching against the mitral valve leading to high values of wall shear stresses (WSSs) with respect to the healthy case.

CONCLUSION

CFD with prescribed wall motion and immersed mitral valve revealed to be an effective tool to quantitatively describe hemodynamics in case of MVR and to compare different regurgitant scenarios. Our findings highlighted in particular the presence of transition to turbulence in the atrium and allowed us to quantify some important cardiac indices such as cardiac output and WSS.

MitraClip as a therapeutic strategy for post-myocardial infarction mitral regurgitation

Mitral regurgitation is a serious complication of post-myocardial infarction, with increasing mortality. Surgery as the primary treatment carries a high risk. MitraClip is a new therapeutic to treat post-myocardial infarction mitral regurgitation. In this case, a 62-year-old male patient suffered from severe heart failure symptoms after emergency coronary intervention and extracorporeal membrane oxygenation support. Based on cardiac echocardiography, severe mitral regurgitation was monitored in this patient. After MitraClip treatment, the patient's condition was gradually improved and discharged successfully. This case highlights that MitraClip is a safe and effective strategy for post-myocardial infarction mitral regurgitation.

NT-proBNP increase during stress echocardiography predicts significant changes in ischemic mitral regurgitation severity in patients qualified for surgical revascularization

BACKGROUND

In many patients, significant changes in ischemic mitral regurgitation (IMR) severity during exercise can be observed independent of the degree of IMR at rest. This study aimed to investigate the correlations between N-terminal fragment B-type natriuretic peptide (NT-proBNP) and echocardiography measurements at rest and at peak exercise in patients with moderate IMR who qualified for surgical revascularization.

METHODS

A total of 100 patients eligible for coronary artery bypass grafting, were included in this prospective study. All patients underwent exercise echocardiography. Additionally, the levels of NT-proBNP were measured at rest and after peak exercise.

RESULTS

A positive correlation of absolute NT-proBNP levels with effective regurgitant orifice area (EROA) were observed and with tricuspid regurgitant peak gradient (TRPG) at peak exercise. Absolute ΔNT-proBNP during exercise and the tenting area at rest were independent predictors of severe IMR at peak exercise. The level of absolute ΔNT-proBNP during exercise and coaptation height at rest were the most important predictors of significant increases in TRPG. The best cutoff value for ΔNT-proBNP as a predictor for increases in EROA at peak exercise was 68.9 pg/mL and to predict an increase in TRPG ≥ 50 mmHg at peak exercise was 68 pg/mL.

CONCLUSIONS

The level of ΔNT-proBNP during exercise was the most important parameter in predicting significant changes in IMR severity and pulmonary pressure. Based on the present data, it can be speculated that integration of the assessment of NT-proBNP at rest and at exercise might improve patient selection for valve surgery.

Transcatheter edge-to-edge repair in patients with mitral regurgitation and cardiogenic shock: a new therapeutic target

PURPOSE OF REVIEW

Cardiogenic shock with significant mitral regurgitation portends a poor prognosis with limited therapeutic options. Herein, we review the available evidence regarding the patient characteristics, management, impact of transcatheter edge-to-edge repair (TEER) on hemodynamics, and clinical outcomes of patients with cardiogenic shock and mitral regurgitation.

RECENT FINDINGS

Several observational studies and systematic reviews have demonstrated the feasibility and safety of TEER in cardiogenic shock complicated by degenerative or functional mitral regurgitation. Surgical interventions for mitral regurgitation remain limited owing to the risk profile of patients in cardiogenic shock. TEER has been studied in both degenerative and functional mitral regurgitation and remains feasible in the critically ill population. Moreover, TEER is associated with reduction in mitral regurgitation and improvement in-hospital and long-term mortality.

SUMMARY

TEER remains a promising therapeutic option in cardiogenic shock complicated by significant mitral regurgitation, but additional research is required to identify patient and procedural characteristics, hemodynamic parameters, and the optimal time for intervention. Moreover, future randomized controlled trials are in progress to evaluate the potential benefit of TEER against medical management in cardiogenic shock and mitral regurgitation.

Clinical, functional and prognostic implications of severe atrial dilation in secondary mitral regurgitation

Objective

Atrial dilation is known to be a poor prognostic indicator. However, its clinical, functional and prognostic implications have not been thoroughly explored in secondary mitral regurgitation (SMR). We sought to describe the implications of severe atrial dilation (SAD) in SMR.

Methods

We included all adult patients with severe SMR due to left ventricle dysfunction (with no organic mitral valve disease) who underwent transthoracic echocardiography between January 2012 and March 2021 at our institution. The concomitant presence of severe left atrial (LA) dilation (>48 mL/m²) defined SADMR (SAD in SMR), and these patients were compared with those without SAD.

Results

A total of 2011 patients were included (mean age 70% and 41% females), with 71% having SADMR. MR severity and ejection fraction were similar between both groups. Patients with SADMR were older, less females and had more diabetes, but similar rates of atrial fibrillation. Mechanistically, they had lower A wave velocity (0.61 vs 0.72 cm/sec, p<0.001) and more impaired LA reservoir strain (9.7% vs 15.5%, p<0.001). Geometrically, SADMR had shallower leaflets’ angulations, lower tenting height, larger annuli and smaller leaflet length/annular diameter ratios (all p<0.001). They underwent fewer MV interventions, although these were associated with better outcomes (log-rank p<0.001). Over the study period, SAD was an independent predictor of mortality (HR 1.26, p=0.04).

Conclusion

SADMR is associated with specific mechanistic and functional alterations and confers a worse prognosis.

Quantified mitral regurgitation and left atrial function in heart failure with reduced ejection fraction: interplay and outcome implications

AIMS

The clinical and prognostic importance of functional mitral regurgitation (FMR) in heart failure patients with reduced ejection fraction (HFrEF) has been highly debated. This study aims to define FMR linkage to cardiovascular (CV) outcomes and the interplay with left atrial (LA) function in a prospective cohort of consecutive HFrEF outpatients.

METHODS AND RESULTS

Overall, 286 consecutive outpatients with chronic HFrEF were prospectively enrolled. FMR was quantified by effective regurgitant orifice area (EROA). Global peak atrial longitudinal strain (PALS) was measured by speckle tracking echocardiography. The primary endpoint was a composite of congestive heart failure hospitalization or CV death. During a mean follow-up of 4.1 ± 1.5 years, the primary endpoint occurred in 99 patients (35%). The spline modelling of the risk by FMR severity showed an excess event risk starting at about the EROA value of 0.1 cm2 . There was a remarkable graded association between the EROA strata, even if tested per 0.1 cm2 increase, and the risk of CV events (hazard ratio [HR] EROA per 0.10 cm2 increase: 1.42, 95% confidence interval [CI] 1.19-1.68; p < 0.0001). EROA ≥0.30 cm2 was associated with CV events regardless of LA function (HR 2.34, 95% CI 1.29-4.19; p = 0.005). Less severe FMR (EROA ≥0.10 cm2 ) was associated with a dismal outcome only in patients with reduced LA function (PALS <14%) (5-year CV event rate 51 ± 4%); conversely, the risk of events was relative reduced when preserved global PALS and FMR coexisted (5-year CV event rate 38 ± 6%).

CONCLUSIONS

Our results refine the independent association between FMR and CV outcome among HFrEF outpatients. Within a moderate EROA range, LA function mitigates the clinical consequences of mitral regurgitation, providing measurable proof of the interplay between regurgitation and LA compliance.

Disproportionate Mitral Regurgitation Determines Survival in Acute Heart Failure

Objectives: To assess the prevalence and impact of mitral regurgitation (MR) on survival in patients presenting to hospital in acute heart failure (AHF) using traditional echocardiographic assessment alongside more novel indices of proportionality.

Background: It remains unclear if the severity of MR plays a significant role in determining outcomes in AHF. There is also uncertainty as to the clinical relevance of indexing MR to left ventricular volumes. This concept of disproportionality has not been assessed in AHF.

Methods: A total of 418 consecutive patients presenting in AHF over 12 months were recruited and followed up for 2 years. MR was quantitatively assessed within 24 h of recruitment. Standard proximal isovelocity surface area (PISA) and a novel proportionality index of effective regurgitant orifice/left ventricular end-diastolic volume (ERO/LVEDV) >0.14 mm²/ml were used to identify severe and disproportionate MR.

Results: Every patient had MR. About 331/418 (78.9%) patients were quantifiable by PISA. About 165/418 (39.5%) patients displayed significant MR. A larger cohort displayed disproportionate MR defined by either a proportionality index using ERO/LVEDV > 0.14 mm²/ml or regurgitant volumes/LVEDV > 0.2 [217/331 (65.6%) and 222/345 (64.3%), respectively]. The LVEDV was enlarged in significant MR−129.5 ± 58.95 vs. 100.0 ± 49.91 ml in mild, [p < 0.0001], but remained within the normal range. Significant MR was associated with a greater mortality at 2 years {44.2 vs. 34.8% in mild MR [hazard ratio (HR) 1.39; 95% CI: 1.01–1.92, p = 0.04]}, which persisted with adjustment for comorbid conditions (HR; 1.43; 95% CI: 1.04–1.97, p = 0.03). Disproportionate MR defined by ERO/LVEDV >0.14 mm²/ml was also associated with worse outcome [42.4 vs. 28.3% (HR 1.62; 95% CI 1.12–2.34, p = 0.01)].

Conclusions: MR was a universal feature in AHF and determines outcome in significant cases. Furthermore, disproportionate MR, defined either by effective regurgitant orifice (ERO) or volumetrically, is associated with a worse prognosis despite the absence of adverse left ventricular (LV) remodeling. These findings outline the importance of adjusting acute volume overload to LV volumes and call for a review of the current standards of MR assessment.

Clinical Trial Registration:https://clinicaltrials.gov/ct2/show/NCT02728739, identifier NCT02728739.

Clinical and Hemodynamic Effects of Percutaneous Edge-to-Edge Mitral Valve Repair in Atrial Versus Ventricular Functional Mitral Regurgitation

The present study aims to assess the clinical and hemodynamic impact of percutaneous edge-to-edge mitral valve repair with MitraClip in patients with atrial functional mitral regurgitation (A-FMR) compared with ventricular functional mitral regurgitation (V-FMR). Mitral regurgitation (MR) grade, functional status (New York Heart Association class), and major adverse cardiac events (MACE; all-cause mortality or hospitalization for heart failure) were evaluated in 52 patients with A-FMR and in 307 patients with V-FMR. In 56 patients, hemodynamic assessment during exercise echocardiography was performed before and 6 months after intervention. MR reduction after MitraClip implantation was noninferior in A-FMR compared with V-FMR (MR grade ≤2 at 6 months in 94% vs 82%, respectively, p <0.001 for noninferiority) and was associated with improvement of functional status (New York Heart Association class ≤2 at 6 months in 90% vs 80%, respectively, p = 0.2). Hemodynamic assessment revealed that cardiac output at 6 months was higher in A-FMR at rest (5.1 ± 1.5 L/min vs 3.8 ± 1.5 L/min, p = 0.002) and during peak exercise (7.9 ± 2.4 L/min vs 6.1 ± 2.1 L/min, p = 0.02). In addition, the reduction in systolic pulmonary artery pressure at rest was more pronounced in A-FMR: Δ SPAP -13.1 ± 15.1 mm Hg versus -2.2 ± 13.3 mm Hg (p = 0.03). MACE rate at follow-up was significantly lower in A-FMR versus V-FMR, with an adjusted odds ratio of 0.46 (95% confidence interval 0.24 to 0.88), which was caused by a reduction in hospitalization for heart failure. In conclusion, percutaneous edge-to-edge mitral valve repair with MitraClip is at least as effective in A-FMR as in V-FMR in reducing MR. However, the hemodynamic improvement and reduction of MACE were significantly better in A-FMR.

The Role of Invasive Hemodynamics in Guiding Contemporary Transcatheter Valvular Interventions

Recent advances in transcatheter interventions have refueled the interest in utilizing invasive hemodynamics in the catheterization laboratory. The authors review contemporary invasive techniques used to confirm valve disease and guide transcatheter valve interventions. They also discuss the available data and the remaining questions on the role of invasive hemodynamics in current practice and in the future.

Stress Echocardiography Protocol for Deciding Type of Surgery in Ischemic Mitral Regurgitation: Predictors of Mitral Regurgitation Recurrence following CABG Alone

PURPOSE

Although coronary artery bypass grafting alone (CABGa), or, with mitral annuloplasty (CABGmp), is considered the best therapeutic strategy for patients with ischemic mitral regurgitation (IMR), some recurrences are still reported. The aim of this study was to evaluate the use of the mitral deformation indices (MDI) as a predictor of recurrence of mitral regurgitation in a 12-month follow-up after CABG alone.

METHODS

A total of 145 patients after myocardial infarction with significant IMR, eligible for CABG, were prospectively enrolled in the study. Mitral valve morphology, left ventricle function, IMR degree as assessed by effective regurgitation orifice area (ERO), myocardial viability, and MDI were assessed prior to surgery. Patients were referred for CABGa (gr.1; n = 90) or CABGmp (gr.2; n = 55) based on clinical assessment, and the results of rest and stress echocardiography (exercise echocardiography and low dose dobutamine echocardiography-DBX). One year after surgery, each patient underwent the evaluation of cardiovascular events. Univariable logistic regression analysis was used to identify the factors of recurrence of IMR in 1 year follow-up. Serial echo examinations were performed in all patients at discharge, and at 1 and 12 months after surgery.

RESULTS

Logistic regression analysis revealed that in CABGa, group preoperative changes of tenting area (TA) and coaptation high (CH) during DBX remained the predictors of the recurrence of IMR in 12 months follow-up. TAdbx > 1 cm2 provided a sensitivity of 90% and specificity of 29%, (AUC 0.6436). The best cut-off value for CHdbx was 0.4 cm (sensitivity 90%, specificity 34%; AUC 0.6432). In both groups (CABGa vs. CABGmp) no significant differences were observed in 12-month mortality (1.2% vs. 0%; p = 1.0), hospitalizations due to the heart failure (HF) exacerbation (5.9% vs. 8.5%; p = 0.72), and in the incidence of the composite endpoint (deaths/CV hosp/stroke) (7% vs. 8.5%; p = 0.742).

CONCLUSIONS

The preoperative assessment of MDI changes during dbx can be used to identify patients with IMR qualified to CABG alone at increased risk of recurrence of IMR in 1 year follow-up. Mitral deformation analysis should be used for a better qualification of patients with IMR to the exact surgical approach.

Hybrid approach for percutaneous mitral valve repair (MitraClip®) followed by minimally invasive direct coronary artery bypass (MIDCAB) in a patient with a high risk constellation

BACKGROUND

We present a 76-year-old poly-morbid male patient suffering from severe ischemic mitral valve regurgitation. A hybrid approach was suggested by the heart team to treat his multifaceted cardiac pathologies.

METHODS

At first percutaneous mitral valve repair with the mitraclip device was performed to reduce surgical risk. This was then followed by minimally invasive direct coronary artery bypass (MIDCAB).

RESULTS

At day 20 Post mitraclip intervention the patient suffered gastrointestinal bleeding which needed argon plasma coagulation (APC)-therapy and multiple blood transfusions. Stage II of the hybrid procedure was executed on post-intervention day 34 by minimally invasive direct coronary artery bypass (MIDCAB) to left anterior descending artery (LAD). Seven days later the patient was discharged. Up to two years of follow-up, the patient is in stable condition, without recurrent cardiac symptoms.

CONCLUSION

Hybrid approach of percutaneous mitral valve repair followed by MIDCAB is an effective minimally invasive treatment for severe ischemic mitral valve regurgitation and coronary artery disease.

Conservative, surgical, and percutaneous treatment for mitral regurgitation shortly after acute myocardial infarction

AIMS 

Severe mitral regurgitation (MR) following acute myocardial infarction (MI) is associated with high mortality rates and has inconclusive recommendations in clinical guidelines. We aimed to report the international experience of patients with secondary MR following acute MI and compare the outcomes of those treated conservatively, surgically, and percutaneously.

METHODS AND RESULTS 

Retrospective international registry of consecutive patients with at least moderate-to-severe MR following MI treated in 21 centres in North America, Europe, and the Middle East. The registry included patients treated conservatively and those having surgical mitral valve repair or replacement (SMVR) or percutaneous mitral valve repair (PMVR) using edge-to-edge repair. The primary endpoint was in-hospital mortality. A total of 471 patients were included (43% female, age 73 ± 11 years): 205 underwent interventions, of whom 106 were SMVR and 99 PMVR. Patients who underwent mitral valve intervention were in a worse clinical state (Killip class ≥3 in 60% vs. 43%, P < 0.01), but yet had lower in-hospital and 1-year mortality compared with those treated conservatively [11% vs. 27%, P < 0.01 and 16% vs. 35%, P < 0.01; adjusted hazard ratio (HR) 0.28, 95% confidence interval (CI) 0.18-0.46, P < 0.01]. Surgical mitral valve repair or replacement was performed earlier than PMVR [median of 12 days from MI date (interquartile range 5-19) vs. 19 days (10-40), P < 0.01]. The immediate procedural success did not differ between SMVR and PMVR (92% vs. 93%, P = 0.53). However, in-hospital and 1-year mortality rates were significantly higher in SMVR than in PMVR (16% vs. 6%, P = 0.03 and 31% vs. 17%, P = 0.04; adjusted HR 3.75, 95% CI 1.55-9.07, P < 0.01).

CONCLUSIONS 

Early intervention may mitigate the poor prognosis associated with conservative therapy in patients with post-MI MR. Percutaneous mitral valve repair can serve as an alternative for surgery in reducing MR for high-risk patients.

Effect of Neprilysin Inhibition for Ischemic Mitral Regurgitation after Myocardial Injury

Angiotensin receptor neprilysin inhibitor (ARNI) treatment reduces functional mitral regurgitation (MR) to a greater extent than angiotensin receptor blocker (ARB) treatment alone, but the mechanism is unclear. We evaluated the mechanisms of how ARNI has an effect on functional MR. After inducing functional MR by left circumflex coronary artery occlusion, male Sprague Dawley rats (n = 31) were randomly assigned to receive the ARNI LCZ696, the ARB valsartan, or corn oil only (MR control). Excised mitral leaflets and left ventricle (LV) were analyzed, and valvular endothelial cells were evaluated focusing on molecular changes. LCZ696 significantly attenuated LV dilatation after 6 weeks when compared with the control group (LV end-diastolic volume, 461.3 ± 13.8 µL versus 525.1 ± 23.6 µL; p < 0.05), while valsartan did not (471.2 ± 8.9 µL; p > 0.05 to control). Histopathological analysis of mitral leaflets showed that LCZ696 strongly reduced fibrotic thickness compared to the control group (28.2 ± 2.7 µm vs. 48.8 ± 7.5 µm; p < 0.05). Transforming growth factor-β and downstream phosphorylated extracellular-signal regulated kinase were also significantly lower in the LCZ696 group. Consequently, excessive endothelial-to-mesenchymal transition (EndoMT) was mitigated in the LCZ696 group compared to the control group and leaflet area was higher (11%) in the LCZ696 group than in the valsartan group. Finally, the MR extent was significantly lower in the LCZ696 group and functional improvement was observed. In conclusion, neprilysin inhibitor has positive effects on LV reverse remodeling and also attenuates fibrosis in MV leaflets and restores adaptive growth by directly modulating EndoMT.

Aortic Valve Replacement in Low-Risk Patients With Severe Aortic Stenosis Outside Randomized Trials

BACKGROUND

Recent randomized trials including low-risk patients showed positive results for transcatheter aortic valve replacement (TAVR) compared to surgical aortic valve replacement (SAVR), but patients with non-tricuspid aortic valve (NTAV), severe coronary artery disease (SevCAD), and those requiring concomitant mitral/tricuspid valve (CMTV) or concomitant ascending aorta replacement (CAAR) interventions were excluded.

OBJECTIVES

This study sought to evaluate the presence and impact of the main clinical variables not evaluated in TAVR versus SAVR trials (NTAV, SevCAD, and CMTV or CAAR intervention) in a large series of consecutive low-risk patients with severe aortic stenosis (SAS) undergoing SAVR.

METHODS

Single-center study including consecutive patients with SAS and low surgical risk (Society of Thoracic Surgeons score of <4%) undergoing SAVR. Baseline, procedural characteristics, and 30-day outcomes were prospectively collected.

RESULTS

Of 6,772 patients with SAS who underwent SAVR between 2000 and 2019, 5,310 (78.4%) exhibited a low surgical risk (mean Society of Thoracic Surgeons score: 1.94 ± 0.87%). Of these, 2,165 patients (40.8%) had at least 1 of the following: NTAV (n = 1,468, 27.6%), SevCAD (n = 307, 5.8%), CMTV (n = 306, 5.8%), and CAAR (n = 560, 10.5%). The 30-day mortality and stroke rates for the overall low-risk SAS cohort were 1.9% and 2.4%, respectively. The mortality rate was similar in the SevCAD (2.6%) and CAAR (2.1%) groups versus the rest of the cohort (odds ratio [OR]: 1.79; 95% confidence interval [CI]: 0.85 to 3.75, and OR: 1.64; 95% CI: 0.88 to 3.05, respectively), lower in the NTAV group (0.9%; OR: 0.42; 95% CI: 0.22 to 0.81), and higher in the CMTV group (5.9%; OR: 2.61; 95% CI: 1.51 to 4.5).

CONCLUSIONS

In a real-world setting, close to one-half of the low-risk patients with SAS undergoing SAVR exhibited at least 1 major criterion not evaluated in TAVR versus SAVR randomized trials. Clinical outcomes were better than or similar to those predicted by surgical scores in all groups but those patients requiring CMTV intervention. These results may help determine the impact of implementing the results of TAVR-SAVR trials in real practice and may inform future trials in specific groups.

Clinical and Echocardiographic Predictors of Reduced Survival in Patient with Functional Mitral Regurgitation

Functional mitral regurgitation (FMR) is associated with a poor outcome in patients with reduced left ventricular ejection fraction (LVEF). Two recent studies of percutaneous mitral valvular repair therapy reported disparate results, likely due in part to variable risk among FMR patients. The aim of this study is to define echocardiographic factors of prognostic significance in FMR patients, and particularly to compare ischemic and nonischemic FMR. We followed three hundred sixteen consecutive patients (age 60 ± 14 years, men 70%) with FMR and LVEF ≤ 35% between January 2010 and December 2015 (mean follow-up 3.7 years). Patients were categorized into ischemic (39.6%) and nonischemic (60.4%). MR was graded according to the American Society of Echocardiography guidelines. Although echo findings were similar between ischemic and nonischemic patient, the incidence of death, heart transplantation (HT), or LVAD implantation was higher in ischemic than in nonischemic patients (Log rank p = 0.001). In age and gender adjusted multivariate (11 variables) Cox regression analysis, left atrium volume index (LAVI) was associated with death, HT, or LVAD with hazard ratio of 2.1 for patients with FMR (p = 0.003). LAVI greater than 48.7 mL/m² predicts adverse outcome in both nonischemic and ischemic FMR (AUC 0.62, p < 0.001). Combined ischemic FMR with LAVI ≥ 48.7 mL/m² had the highest incident rate of all groups. In conclusion, despite similar LV function and MR severity, ischemic FMR patients had higher mortality than nonischemic patients. Of all echocardiographic parameters, an LAVI ≥ 48.7 mL/m² predicted adverse clinical outcome.

Prior angina reduces ıschemic mitral regurgitation in patients with ST-Elevation myocardial ınfarction, role of ıschemic preconditioning

Mitral regurgitation may develop due to left ventricular (LV) remodeling within 3 months following acute myocardial infarction (AMI) and is called ischemic mitral regurgitation (IMR). Ischemic preconditioning (IPC) has been reported as the most important mechanism of the association between prior angina and the favorable outcome. The aim of this study was to investigate the effect of prior angina on the development and severity of IMR at 3rd month in patients with ST elevation MI (STEMI). Fourty five (45) patients admitted with STEMI and at least mild IMR, revascularized by PCI were enrolled. According to presence of prior angina within 72 h before STEMI, patients were then divided into two groups as angina (+) (n:26; 58%) and angina (-) (n:19; 42%). All patients underwent 2D transthoracic echocardiography at 1st, 3rd days and 3rd month. IMR was evaluated by proximal isovelocity surface area (PISA) method: PISA radius (PISA-r), effective regurgitant orifice area (EROA), regurgitant volume (Rvol). LV ejection fraction (EF %) was calculated by Simpson's method. High sensitive troponin T (hs-TnT), creatine phosphokinase myocardial band (CK-MB) and N-terminal pro-brain natriuretic peptid (NTpro-BNP) levels were compared between two groups. Although PISA-r, EROA and Rvol were similar in both groups at 1st and 3rd days, all were significantly decreased (p = 0.012, p = 0.007, p = 0.011, respectively) and EF was significantly increased (p< 0 .001) in angina (+) group at 3rd month. NTpro-BNP and hs-TnT levels at 1st day and 3rd month were similar, however CK-MB level at 3rd month was found to be significantly lower in the angina (+) group (p = 0.034). At the end of the 3rd month, it was observed that the severity of IMR evaluated by PISA method was decreased and EF increased significantly in patients who defined angina within 72 h prior to STEMI, suggesting a relation with IPC.

Significant functional mitral regurgitation affects left atrial function in heart failure patients: haemodynamic correlations and prognostic implications

AIMS

Functional mitral regurgitation (FMR) is a well-known pathophysiological factor in heart failure (HF) patients, and left atrial function (LAF) is a novel determinant of clinical status and outcome in this setting. However, little is known about the pathophysiological role of FMR on LAF in HFrEF patients. Aim of this study is to explore the possible interplay between the severity of FMR and LAF in heart failure with reduce ejection fraction (HFrEF) patients and their possible consequences.

METHODS AND RESULTS

We studied 97 consecutive patients with FMR classified in two groups: mild-to-moderate MR ore less (FMR group, n = 38) and moderate-to-severe or more (SFMR group, n = 59). Using the phasic method, left atrial contractile, conduit, reservoir, and total emptying function (TLAEF) were calculated to assess LAF. SFMR group showed significantly lower values of LAF compared to FMR group. LA dysfunction (LA-dys) was defined for TLAEF values below the median and groups divided in four subgroups based on its presence. Patient with LA-Dys in SFMR group showed a worse clinical status, higher incidence of right ventricular dysfunction (RV-Dys), and pulmonary hypertension (PH), and a significant worse clinical survival compared to all other groups.

CONCLUSION

In our study, the survival was significantly lower in SFMR/LA-Dys+ group. Furthermore, LA-Dys was strongly related with worse clinical status and higher incidence of PH and RV-Dys. These results suggest that in patients with SFMR and HFrEF, LA-Dys may represent both a marker of more advanced disease and a novel prognostic factor.

Proportionate or disproportionate secondary mitral regurgitation: how to untangle the Gordian knot?

Recent randomised percutaneous mitral intervention trials in patients with heart failure with secondary mitral regurgitation (SMR) have yielded contrasting results. A 'relative load' or 'proportionality' conceptual framework for SMR has been proposed to partly explain the disparate results. The rationale behind the framework is that SMR depends on the left ventricular dimension and not vice versa. In this review, we provide an in-depth analysis of the proportionality parameters used in this framework and also discuss the regurgitant fraction. We also consider haemodynamic observations in SMR that may affect the interpretation and comparisons among proportionality parameters. The conclusion is that the proportionality concept remains hypothetical and requires prospective validation before envisaging its use at individual patient level for risk stratification or therapeutic decision-making.

Redistribution of cardiac output during exercise by functional mitral regurgitation in heart failure: compensatory O2 peripheral uptake to delivery failure

This is an analysis involving 134 heart failure patients with reduced ejection fraction versus 80 controls investigated during functional evaluation with gas exchange and hemodynamic, addressing the severe mitral regurgitation phenotype and testing the hypothesis that the backward cardiac output redistribution to the lung during exercise impairs delivery and overexpresses peripheral extraction. This information is new and has important implications in the management of heart failure.

Cost-effectiveness of coronary artery bypass grafting plus mitral valve repair versus coronary artery bypass grafting alone for moderate ischemic mitral regurgitation

OBJECTIVE

The Cardiothoracic Surgical Trials Network reported that left ventricular reverse remodeling at 2 years did not differ between patients with moderate ischemic mitral regurgitation randomized to coronary artery bypass grafting plus mitral valve repair (n = 150) or coronary artery bypass grafting alone (n = 151). To address health resource use implications, we compared costs and quality-adjusted survival.

METHODS

We used individual patient data from the Cardiothoracic Surgical Trials Network trial on survival, hospitalizations, quality of life, and US hospitalization costs to estimate cumulative costs and quality-adjusted life years. A microsimulation model was developed to extrapolate to 10 years. Bootstrap and deterministic sensitivity analyses were performed to address uncertainty.

RESULTS

In-hospital costs were $59,745 for coronary artery bypass grafting plus mitral valve repair versus $51,326 for coronary artery bypass grafting alone (difference $8419; 95% uncertainty interval, 2259-18,757). Two-year costs were $81,263 versus $67,341 (difference 13,922 [2370 to 28,888]), and quality-adjusted life years were 1.35 versus 1.30 (difference 0.05; -0.04 to 0.14), resulting in an incremental cost-effectiveness ratio of $308,343/quality-adjusted life year for coronary artery bypass grafting plus mitral valve repair. At 10 years, its costs remained higher ($107,733 vs $88,583, difference 19,150 [-3866 to 56,826]) and quality-adjusted life years showed no difference (-0.92 to 0.87), with 5.08 versus 5.08. The likelihood that coronary artery bypass grafting plus mitral valve repair would be considered cost-effective at 10 years based on a cost-effectiveness threshold of $100K/quality-adjusted life year did not exceed 37%. Only when this procedure reduces the death rate by a relative 5% will the incremental cost-effectiveness ratio fall below $100K/quality-adjusted life year.

CONCLUSIONS

The addition of mitral valve repair to coronary artery bypass grafting for patients with moderate ischemic mitral regurgitation is unlikely to be cost-effective. Only if late mortality benefits can be demonstrated will it meet commonly used cost-effectiveness criteria.

The Use of MitraClip in Secondary Mitral Regurgitation and Heart Failure

Secondary (also known as functional) mitral regurgitation (MR) has increased substantially over the last several decades due to an increase in the prevalence of dilated cardiomyopathy (ischemic and non-ischemic). Mortality and morbidity in patients with dilated cardiomyopathy is much greater when associated with MR as compared to without MR. MR will result in further left ventricular (LV) volume overload, LV dilation, and pupillary muscle displacement resulting in deterioration of the severity of MR leading to a vicious cycle. Optimization of heart failure medical therapy, and cardiac resynchronization therapy for those that qualify, can improve severity of MR; however, significant MR will persist in certain patients. Transcatheter mitral valve repair to treat significant MR using the MitraClip (Abbott, Menlo Park, California), which grasps and coapts the posterior and anterior mitral valve leaflets, in appropriately selected patients with dilated cardiomyopathy and secondary MR has been shown to improve quality of life and prolong survival.

An Observational Study of QTc Prolongation in Critically Ill Patients: Identification of Incidence and Predictors

AIMS

Despite the importance of abnormal QTc interval values in intensive care unit (ICU) patients, there is a paucity of information on this topic. The current study was designed to identify the incidence and predictors of QTc prolongation in medical (M), surgical (S), and emergency (E) ICUs.

MATERIALS AND METHODS

A prospective observational study was conducted for 6 months. Patients more than 18 years old who admitted to MICU, SICU, and EICU were included in the study. Electrocardiogram (ECG) was taken on day 1, 3, and 5 of ICU admission. The QTc intervals >460 ms in male and >470 ms in female and increased >60 ms above baseline were considered QTc prolongation. Comparative analysis was done between two groups of patients (normal vs prolonged QTc). Logistic regression models were carried out to determine the predictors of QTc prolongation.

RESULTS

Incidence of QTc prolongation was 6.5, 9.8, and 15.7% on day 1, 3, and 5 of ICU admission, respectively. On day 1, the history of alcohol addiction and the reason of ICU admission were associated with a prolonged QTc. A significant association was demonstrated between administration of azithromycin and QTc prolongation on day 3. High serum creatinine and hospitalization in EICU were predictors of QTc prolongation on day 5 of ICU admission.

CONCLUSION

The QTc prolongation is relatively common among patients admitted to ICUs and its incidence increases with increasing length of hospital stay. Predictors of QTc prolongation may be affected by the duration of ICU admission. Physicians should consider these predictors particularly before prescribing QTc-prolonging drugs.

HOW TO CITE THIS ARTICLE

Farzanegan B, Hosseinpoor Z, Baniasadi S, Seyyedi SR, Rajabi M. An Observational Study of QTc Prolongation in Critically Ill Patients: Identification of Incidence and Predictors. Indian J Crit Care Med 2020;24(4):270-275.

Meta-analysis of results of subvalvular repair for severe ischemic mitral regurgitation

BACKGROUND AND AIM OF THE STUDY

The aim of this meta-analysis was to compare short- and long-term outcomes of patients undergoing mitral annuloplasty (MA) with or without papillary muscle surgery (PMS) for the treatment of ischemic mitral regurgitation (IMR).

METHODS

A systematic review and meta-analysis in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement were performed.

RESULTS

Nine studies met the inclusion criteria. This meta-analysis identified 478 patients: 228 patients underwent MA alone and 250 patients underwent concomitant PMS. Early mortality was similar between two groups (odds ratio [OR] 1.14, 95% confidence interval [CI], 0.51-2.53; P = .75). PMS was associated at follow-up with a higher freedom from cardiac-related events (P = .050); moreover, although both surgical techniques had a positive impact on ventricular remodeling, the PMS group showed a significant higher reduction of left ventricle end-diastolic diameter (OR, 4.89, 95% CI, 2.77-7.01; P < .001) and left ventricle end-systolic diameter values (OR, 4.11, 95% CI, 1.98-6.24; P < .001). Finally, PMS compared with MA alone was associated with a significant reduction of recurrent mitral regurgitation at follow-up (OR, 3.25, 95% CI, 1.60-6.59; P = .001).

CONCLUSIONS

This meta-analysis demonstrated superiority in terms of ventricular remodeling of a combined approach encompassing PMS and MA over MA alone in IMR. Moreover, the association of subvalvular surgery with restrictive MA decreases the incidence of mitral regurgitation recurrence and cardiac-related events at follow-up.

Patients over 70 years of age with moderate ischemic mitral regurgitation undergoing surgical revascularization plus mitral valve repair: insights from a single-center study of propensity-matched data

Background

Elderly patients, compared with the young, have a higher burden of surgical risk factors with reduced functional capacity and increased comorbidities conditions, and may have worse clinical outcomes. So far, few reports have focused on clinical outcomes of patients over 70 years of age with moderate chronic ischemic mitral regurgitation (IMR) undergoing mitral valve repair at the time of coronary artery bypass grafting (CABG). This single-center study of propensity-matched data attempts to answer a question: compared with patients with age of 70 or less, whether patients over 70 years of age with moderate IMR undergoing CABG plus mitral valve repair receive poor outcomes.

Methods

All eligible patients were included in this study and were entered into either an elderly group (n=142) or a control group (n=182) according to patients' age. In-hospital outcomes (consisting of surgical mortality and major postoperative morbidity) and midterm clinical outcomes (including all-cause mortality and recurrent mitral regurgitation) were compared after propensity score matching (1:1).

Results

Using propensity-score matching, 103 pairs of patients were successfully established in a 1:1 ratio. No significant differences between the two matched groups were found with regard to surgical mortality (5.8% vs. 3.9%, P=0.754) and major postoperative morbidity. A total of 184 patients (91 in the elderly group and 93 in the control group) received regular follow-up visit with the median duration of 38 months [interquartile range (IQR), 27-56 months]. There were not any significant differences between the two matched groups regarding overall survival and recurrent IMR-free survival (stratified log-rank P=0.185 and stratified log-rank P=0.453, respectively). The elderly group as compared to the control group did not affect midterm mortality via cox proportional hazard regression (propensity score adjusted hazard ratio, 1.143; 95% confidence interval, 0.761-1.943; P=0.285).

Conclusions

Patients over 70 years of age with moderate chronic IMR undergoing combined CABG and mitral valve repair may receive favorable in-hospital and midterm clinical outcomes.

Papillary muscle intervention vs mitral ring annuloplasty in ischemic mitral regurgitation

Background and Aims

The main pathophysiological factor of chronic ischemic mitral regurgitation (MR) is the outward displacement of the papillary muscles (PMs) leading to leaflet tethering. For this reason, papillary muscle intervention (PMI) in combination with mitral ring annuloplasty (MRA) has recently been introduced into clinical practice to correct this displacement, and to reduce the recurrence of regurgitation.

Methods

A meta‐analysis was conducted comparing the outcomes of PMI and MRA performed in combination vs MRA performed alone, in terms of MR recurrence and left ventricular reverse remodeling (LVRR). A meta‐regression was carried out to investigate the impact of the type of PMI procedure on the outcomes.

Results

MR recurrence in patients undergoing both PMI and MRA was lower than in those who only had MRA (log incidence rate ratio, −0.66; lower‐upper limits, −1.13 to 0.20; I² = 0.0%; p = .44; Egger's test: intercept 0.35 [−0.78 to 1.51]; p = .42).

The group with both PMI and MRA and that with only MRA showed a slightly higher reduction in left ventricular diameters (−5.94%; −8.75% to 3.13%,). However, in both groups, LVRR was <10%. No difference was detected between PM relocation/repositioning and papillary muscle approximation in terms of LVRR (p = .33).

Conclusions

Using PMI and MRA together has a lower MR recurrence than using MRA alone. No significant LVRR was observed between the two groups nor between the PMI techniques employed.

Treatment of Functional Mitral Regurgitation in Heart Failure

PURPOSE OF REVIEW

To analyze the current state of the art of functional mitral regurgitation (FMR) treatment.

RECENT FINDINGS

The first-line treatment of severe FMR consists of guideline medical therapy (GMT) and resynchronization therapy when indicated; the impact of new medical therapies like sacubitril/valsartan needs further assessment. Valvular intervention may be considered in FMR symptomatic patients despite GMT, and can be performed surgically or percutaneously. MitraClip is a safe percutaneous procedure associated with symptoms improvement. Recently, the COAPT trial showed superior outcomes for MitraClip versus GMT contrasting the MITRA-FR trial which showed no benefit of MitraClip compared with GMT. These results should be interpreted as complementary rather than opposite. The COAPT trial provided a "proof of concept" that percutaneous treatment of severe FMR in patients without too advanced left ventricular disease translates into a prognostic benefit. Careful patient selection will play a critical role in defining the clinical niche for successful interventions.

Long-term effect of atrial fibrillation on the evolution of mitral and tricuspid valve regurgitation

Objective: The present study aims to identify the long-term effects of atrial fibrillation (AF) on atrial remodelling and on the progression of mitral/tricuspid valve regurgitation (MR/TR). Methods: The severity of MR/TR was assessed by the colour jet area and by multi-integrative approach at baseline and after a period of 65 ± 10 months in 37 patients with permanent AF, in 80 patients with non-permanent AF (of whom 43 were treated with ablation) and in 53 control patients with sinus rhythm. Results: At baseline, AF patients had larger MR jet areas than control patients. At follow up, progression of MR, expressed as delta MR jet area, was 0.05 ± 1.3 cm² in the control group, 0.73 ± 2.1 cm² in the non-permanent AF group and 1.95 ± 3.6 cm² in the permanent AF group (p = .001). Severe MR at follow up was observed in 0%, 2.5%, 8%, respectively. There was a significant positive correlation between progression of MR and increase of left atrium volume (r = 0.31, p < .001). After adjustment for baseline clinical and echocardiographic parameters, permanent AF remained independently associated with the progression of MR. Although rhythm control was better with AF ablation than with medical treatment only, the MR evolution was similar. Comparable findings, albeit less pronounced, were observed for the association between of AF and TR progression. Conclusions: The presence of longstanding AF is associated with a significant progression of MR/TR mainly due to atrial remodelling. Our data showed a beneficial effect of sustained rhythm control, either medically or by ablation, on MR/TR progression.

Left ventricular geometry predicts optimal response to percutaneous mitral repair via MitraClip: Integrated assessment by two- and three-dimensional echocardiography

OBJECTIVES

To assess impact of left ventricular (LV) chamber remodeling on MitraClip (MClp) response.

BACKGROUND

MitraClip is the sole percutaneous therapy approved for mitral regurgitation (MR) but response varies. LV dilation affects mitral coaptation; determinants of MClp response are uncertain.

METHODS

LV and mitral geometry were quantified on pre- and post-procedure two-dimensional (2D) transthoracic echocardiography (TTE) and intra-procedural three-dimensional (3D) transesophageal echocardiography (TEE). Optimal MClp response was defined as ≤mild MR at early (1-6 month) follow-up.

RESULTS

Sixty-seven degenerative MR patients underwent MClp: Whereas MR decreased ≥1 grade in 94%, 39% of patients had optimal response (≤mild MR). Responders had smaller pre-procedural LV end-diastolic volume (94 ± 24 vs. 109 ± 25 mL/m2 , p = 0.02), paralleling smaller annular diameter (3.1 ± 0.4 vs. 3.5 ± 0.5 cm, p = 0.002), and inter-papillary distance (2.2 ± 0.7 vs. 2.5 ± 0.6 cm, p = 0.04). 3D TEE-derived annular area correlated with 2D TTE (r = 0.59, p < 0.001) and was smaller among optimal responders (12.8 ± 2.1 cm2 vs. 16.8 ± 4.4 cm2 , p = 0.001). Both 2D and 3D mitral annular size yielded good diagnostic performance for optimal MClp response (AUC 0.73-0.84, p < 0.01). In multivariate analysis, sub-optimal MClp response was associated with LV end-diastolic diameter (OR 3.10 per-cm [1.26-7.62], p = 0.01) independent of LA size (1.10 per-cm2 [1.02-1.19], p = 0.01); substitution of mitral annular diameter for LV size yielded an independent association with MClp response (4.06 per-cm2 [1.03-15.96], p = 0.045).

CONCLUSIONS

Among degenerative MR patients undergoing MClp, LV and mitral annular dilation augment risk for residual or recurrent MR, supporting the concept that MClp therapeutic response is linked to sub-valvular remodeling.

Equine Acquired Valvular Disease

Degenerative myxomatous disease is common and is associated with aging. Poor prognostic indicators for equine aortic regurgitation specifically include ventricular ectopy, increased pulse pressure, and hyperkinetic pulses. Valvular prolapse is a functional abnormality diagnosed echocardiographically, about which knowledge is limited. A better understanding of its role in valvular regurgitation is needed. Infective endocarditis presents with fever and other systemic signs accompanying valvular regurgitation. The prognosis is poor, warranting aggressive therapy. Other forms of valvular disease occur rarely, but often presenting with severe regurgitation. Management of horses with valvular disease is focused on assessment of severity and regular clinical, echocardiographic, and electrocardiographic monitoring.

Ischemic Mitral Regurgitation: Repair, Replacement or Nothing

The treatment strategy for ischemic mitral regurgitation (MR) continues to evolve with the completion of multicenter trials and the advancement of surgical and percutaneous interventional techniques. This review defines ischemic MR, outlines key clinical trials that assess surgical and interventional approaches, and reports the main elements of recent national guidelines for decision making in treatment of ischemic MR. New findings in percutaneous mitral valve repair and replacement for ischemic MR will also be described. Effective perioperative care of patients with ischemic MR requires clinicians to be well versed in the most up-to-date recommendations and emerging technological developments.

Contemporary Management of Ischemic Mitral Regurgitation: A Review

Ischemic mitral regurgitation occurs relatively frequently in patients with coronary artery disease and is associated with an increased long-term risk. The pathophysiology of ischemic mitral regurgitation is vexing and poses both diagnostic and therapeutic challenges, leading to the need for a comprehensive, multidisciplinary approach. The management is largely focused on medical therapy, and for those eligible, coronary revascularization or cardiac resynchronization therapy may be considered. In select patients, mitral valve surgery or catheter-based therapy may be undertaken with careful consideration of the underlying pathophysiology, surgical risk, and expected long-term outcomes. The appropriate evaluation of patients with ischemic mitral regurgitation involves a careful multidisciplinary approach that carefully considers symptomatology, the etiology and severity of the mitral regurgitation, and the assessment of comorbidities and operative risk to individualize the care of these patients.

Repair or replacement for severe ischemic mitral regurgitation: A meta-analysis

BACKGROUND

The best surgical option for severe ischemic mitral regurgitation (IMR) is still controversial. The aim of this study was to perform a meta-analysis to compare the clinical outcomes of mitral valve repair (MVP) with replacement (MVR).

METHODS

A literature search was conducted in PubMed, Embase, and Medline using the terms "ischemic mitral regurgitation" and "repair or annuloplasty or reconstruction" and "replacement" in the title/abstract field. The primary outcomes of interest were perioperative mortality and long-term survival. Secondary outcomes were mitral regurgitation (MR) recurrence and reoperation.

RESULTS

Of 276 studies, 13 studies met the inclusion and exclusion criteria. A total of 1993 patients were included in these studies, consisting of 1259 (63%) repair cases, and 734 (37%) replacement cases. Perioperative mortality was lower with MVP compared with MVR [OR 0.61; (95% CI, 0.43-0.87; P < .05)]. There was no difference with respect to long-term survival [HR 0.75; (95% CI, 0.52-1.09; P = .14)] and reoperation [OR 0.77; (95% CI, 0.38-1.57; P = .47)]. MVP is associated with a higher recurrence of MR [OR = 4.09; (95% CI, 1.82-9.19; P < .001)].

CONCLUSION

MVP is associated with a lower perioperative mortality but a higher recurrence of MR compared with MVR for severe IMR. No differences were found with respect to long-term survival and reoperation.

Mitral annuloplasty ring flexibility preferentially reduces posterior suture forces

Annuloplasty ring repair is a common procedure for the correction of mitral valve regurgitation. Commercially available rings vary in dimensions and material properties. Annuloplasty ring suture dehiscence from the native annulus is a catastrophic yet poorly understood phenomenon that has been reported across ring types. Recognizing that sutures typically dehisce from the structurally weaker posterior annulus, our group is conducting a multi-part study in search of ring design parameters that influence forces acting on posterior annular sutures in the beating heart. Herein, we report the effect of ring rigidity on suture forces. Measurements utilized custom force sensors, attached to annuloplasty rings and implanted in normal ovine subjects via standard surgical procedure. Tested rings included the semi-rigid Physio (Edwards Lifesciences) and rigid and flexible prototypes of matching geometry. While no significant differences due to ring stiffness existed for sutures in the anterior region, posterior forces were significantly reduced with use of the flexible ring (rigid: 1.95 ± 0.96 N, semi-rigid: 1.76 ± 1.19 N, flexible: 1.04 ± 0.63 N; p < 0.001). The ratio of anterior to posterior F_C scaled positively with increasing flexibility (p < 0.001), and posterior forces took more time to reach their peak load when a flexible ring was used (p < 0.001). This suggests a more rigid ring enables more rapid/complete force equilibration around the suture network, transferring higher anterior forces to the weaker posterior tissue. For mitral annuloplasties requiring ring rigidity, we propose a ring design concept to potentially disrupt this force transfer and improve suture retention.

Mitral valve interventions in heart failure

Secondary mitral regurgitation (MR) results from left ventricular dilatation and dysfunction. Quantification of secondary MR is challenging because of the underlying myocardial disease. Clinical and echocardiographic evaluation requires a multi‐parametric approach. Severe secondary MR occurs in up to one‐fourth of patients with heart failure with reduced ejection fraction, which is associated with a mortality rate of 40% to 50% in 3 years. Percutaneous edge‐to‐edge mitral valve repair (MitraClip) has emerged as an alternative to surgical valve repair to improve symptoms, functional capacity, heart failure hospitalizations, and cardiac haemodynamics. Further new transcatheter strategies addressing MR are evolving. The Carillion, Cardioband, and Mitralign devices were designed to reduce the annulus dilatation, which is a frequent and important determinant of secondary MR. Several transcatheter mitral valve replacement systems (Tendyne, CardiAQ‐Edwards, Neovasc, Tiara, Intrepid, Caisson, HighLife, MValve System, and NCSI NaviGate Mitral) are emerging because valve replacement might be more durable compared with valve repair. In small studies, these interventional therapies demonstrated feasibility and efficiency to reduce MR and to improve heart failure symptoms. However, neither transcatheter nor surgical mitral valve repair or replacement has been proven to impact on the prognosis of heart failure patients with severe MR, which remains high with a mortality rate of 14–20% at 1 year. To date, the primary indication for treatment of secondary severe MR is the amelioration of symptoms, reinforcing the value of a Heart Team discussion. Randomized studies to investigate the treatment effect and long‐term outcome for any transcatheter or surgical mitral valve intervention compared with optimized medical treatment are urgently needed and underway.

Surgical treatment of secondary mitral regurgitation: is repair a reasonable option?

Background

The optimal approach for treating secondary mitral regurgitation (MR) is debated. Since annuloplasty alone has resulted in 30% or more recurrent MR in the mid-term, recent studies suggest mitral valve replacement. However, subvalvular repair strategies as an adjunct to annuloplasty in order to prevent recurrent MR due to ongoing left ventricle (LV) remodeling are becoming increasingly popular. In this study we present short term results of patients with secondary MR who underwent mitral repair using a novel subvalvular repair approach and address the questions whether mitral repair is a reasonable option in these patients.

Methods

Ten patients presenting with functional MR underwent ring annuloplasty and a subvalvular approximation of the papillary muscles using a technique where the distance between both papillary muscles was adjusted with a Polytetrafluoroethylene (PTFE) string during the saline test (Ring-Noose-String technique).

Results

Nine of ten patients had none-mild MR while in one patient mild-moderate MR due to ongoing leaflet tethering was diagnosed at discharge. In this patient, insufficient adjustment of the PTFE string is hypothesized as the primary mechanism for suboptimal repair. There were no complications related to the novel surgical technique. No patient died during the follow up period.

Conclusions

The Ring-Noose-String technique provides acceptable repair results in the short term. A longer follow-up is needed to proof its long-term efficacy. Subvalvular techniques such as this may allow a durable repair in patients with secondary MR.