Estimating postoperative left ventricular volume: Identification of responders to surgical ventricular reconstruction

Mid-term outcomes of surgical aortic valve replacement using a mosaic porcine bioprosthesis with concomitant mitral valve repair

This study retrospectively evaluated the mid-term outcomes of surgical aortic valve replacement (SAVR) using a stented porcine aortic valve bioprosthesis (Mosaic; Medtronic Inc., Minneapolis, MN, USA) with concomitant mitral valve (MV) repair. From 1999 to 2014, 157 patients (median [interquartile range] age, 75 [70-79] years; 47% women) underwent SAVR with concomitant MV repair (SAVR + MV repair), and 1045 patients (median [interquartile range] age, 76 [70-80] years; 54% women) underwent SAVR only at 10 centers in Japan as part of the long-term multicenter Japan Mosaic valve (J-MOVE) study. The 5-year overall survival rate was 81.5% ± 4.1% in the SAVR + MV repair group and 85.1% ± 1.4% in the SAVR only group, and the 8-year overall survival rates were 75.2% ± 5.7% and 78.1% ± 2.1%, respectively. Cox proportional hazards analysis showed no significant difference in the survival rates between the two groups (hazard ratio, 0.87; 95% confidence interval, 0.54-1.40; P = 0.576). Among women with mild or moderate mitral regurgitation who were not receiving dialysis, those who underwent SAVR + MV repair, were aged > 75 years, and had a preoperative left ventricular ejection fraction of 30-75% tended to have a lower mortality risk. In conclusion, this subgroup analysis of the J-MOVE cohort showed relevant mid-term outcomes after SAVR + MV repair.

AATS 2023: Left ventricular restoration with scar exclusion in the surgical treatment for ischemic heart failure

OBJECTIVE

Post-infarction myocardial scar as detected by cardiac magnetic resonance (CMR) is associated with adverse left ventricular (LV) remodeling and negatively affects the prognosis. We sought to analyze the impact of left ventricular restoration (LVR) with asynergic scar exclusion on long-term outcomes for patients with ischemic heart failure (IHF).

METHODS

From January 2005, 134 consecutive patients with IHF underwent scar-exclusive LVR. Among the 131 survivors, 108 patients had paired late gadolinium enhancement (LGE)-CMR preoperatively and one year after, and represent the study population. Patients were divided into two groups according to whether their post-LVR residual percentage of scarred LV perimeter was <35% (%Scar <35; n = 55) or more (%Scar ≥35; n = 53). We compared the two groups, by looking at LGE-CMR outcomes, and at long-term survival and cardiac event (hospitalization for cardiac causes)-free survival.

RESULTS

Postoperative LV end-systolic volume index decreased significantly and ejection fraction increased with significant increase in stroke volume index (P < 0.05 for both). LV diastolic function of the left atrial volume index was significantly improved in patients with residual %Scar <35 than in those with %Scar ≥35 (P interaction = 0.005). Median survival in patients with residual %Scar <35 and ≥ 35 were 8.3 (4.5-12.2) years and 6.8 (1.8-11.8) years respectively (P = 0.106). Median cardiac event-free survival in patients with %Scar <35 and ≥ 35 were 8.0 (3.9-12.1) years and 4.8 (0.8-8.8) years respectively (P < 0.001).

CONCLUSIONS

Scar-exclusive LVR yielded sustainable improvement in LV function and favorable long-term survival regardless of the extent of residual scar. The LVR should be performed to attain scar exclusion in the surgical treatment for IHF, which in turn might protectively affect LV diastolic function and cardiac event-free survival.

Elucidating the mechanisms underlying left ventricular function recovery in patients with ischemic heart failure undergoing surgical remodeling: A 3-dimensional ultrasound analysis

OBJECTIVE

The study objective was to elucidate the mechanisms of left ventricle functional recovery in terms of endocardial contractility and synchronicity after surgical ventricular reconstruction.

METHODS

Real-time 3-dimensional transthoracic echocardiography was performed on 20 patients with anterior left ventricle remodeling and ischemic heart failure before surgical ventricular reconstruction and at 6-month follow-up, and on 15 healthy controls matched by age and body surface area. Real-time 3-dimensional transthoracic echocardiography datasets were analyzed through TomTec software (4D LV-Analysis; TomTec Imaging Systems GmbH, Unterschleissheim, Germany): Left ventricle volumes, ejection fraction, and global longitudinal strain were computed; the time-dependent endocardial surface yielded by 3-dimensional speckle-tracking echocardiography was postprocessed through in-house software to quantify local systolic minimum principal strain as a measure of fiber shortening and mechanical dispersion as a measure of fiber synchronicity.

RESULTS

Compared with controls, patients with heart failure before surgical ventricular reconstruction showed lower ejection fraction (P < .0001) and significantly impaired mechanical dispersion (P < .0001) and minimum principal strain (P < .0001); the latter worsened progressively from left ventricle base to apex. After surgical ventricular reconstruction, global longitudinal strain improved from -6.7% to -11.3% (P < .0001); mechanical dispersion decreased in every left ventricle region (P ≤ .017) and mostly in the basal region, where computed mechanical dispersion values were comparable to physiologic values (P ≥ .046); minimum principal strain improved mostly in the basal region, changing from -16.6% to -22.3% (P = .0027).

CONCLUSIONS

At 6-month follow-up, surgical ventricular reconstruction was associated with significant recovery in global left ventricle function, improved mechanical dispersion indicating a more synchronous left ventricle contraction, and improved left ventricle fiber shortening mostly in the basal region, suggesting the major role of the remote myocardium in enhancing left ventricle functional recovery.

Effects of trehalose on recurrence of remodeling after ventricular reconstruction in rats with ischemic cardiomyopathy

Recurrence of left ventricular (LV) remodeling after surgical ventricular reconstruction (SVR) for ischemic cardiomyopathy has been reported to be partially attributed to autophagy. We aimed to examine the effects of trehalose, an autophagy inducer, on the recurrence of LV remodeling after SVR. After SVR in rats with ICM, trehalose was orally administered. The changes in LV end-diastolic dimension (LVEDD) and fractional shortening (FS) were evaluated. The activation of myocardial autophagy was also estimated by autophagy markers: microtubule-associated light chain 3 II (LC3-II) and p62; the former usually increases and the latter decreases if autophagy is activated. Significant LV reverse remodeling was observed early after SVR. On the other hand, the 28th postoperative day SVR + trehalose was associated with smaller LVEDD and better FS than SVR alone (LVEDD, P = 0.043; FS, P < 0.01). LC3-II increased comparably in both groups, while p62 was significantly lower in the SVR + trehalose group than in the SVR alone group (P < 0.01). In conclusion, trehalose attenuated the recurrence of LV remodeling and changed autophagy markers after SVR in rats with ICM. Trehalose may be a candidate for adjuvant therapy to retain the effects of SVR.

Reduction of tethering distance by papillary muscle tugging approximation with mitral valve replacement for non-ischemic functional mitral regurgitation induces left ventricular reverse remodeling

BACKGROUND

Functional mitral regurgitation (FMR) is caused by left ventricular (LV) remodeling and subsequent tethering of the mitral valve (MV). If LV remodeling is irreversibly advanced, it could not be attenuated by the MV procedure alone, although the additional subvalvular procedure could induce LV reverse remodeling by forcibly reducing MV tethering. This study aimed to assess the anti-tethering effect of papillary muscle tugging approximation (PMTA) on LV reverse remodeling after mitral valve replacement (MVR) for non-ischemic FMR.

METHODS

The study subjects were 19 patients who underwent MVR with and without PMTA [MVR + PMTA (n = 11) and MVR alone (n = 8), respectively] for non-ischemic FMR. The tethering distance (TD) and LV end-systolic volume (ESV) at the preoperative, postoperative, and follow-up periods were assessed in terms of their correlation and time-dependent changes. The intra-LV energy efficiency was also evaluated through vector flow mapping analysis.

RESULTS

TD and ESV were comparable between both procedures preoperatively and did not change after MVR alone. In MVR + PMTA, however, a significant decrease was identified in TD and ESV at the early postoperative and follow-up periods, respectively [TD = 48, 30, and 31 mm (p < 0.001) and ESV = 159, 133, and 82 mL (p < 0.001) at the preoperative, postoperative, and follow-up periods, respectively]. Finally, at follow-up, the extent of change from the preoperative value in ESV significantly correlated with that in TD (ρ = 0.81, p < 0.001 for overall; ρ = 0.93, p < 0.001 for MVR + PMTA; ρ = 0.86, p = 0.011 for MVR alone). The ratio of TD to ESV was also significantly correlated with systolic energy loss to LV stroke work after MVR + PMTA (ρ = 0.81, p = 0.015).

CONCLUSIONS

PMTA for non-ischemic FMR could induce LV reverse remodeling depending on the extent of postoperative TD reduction. A smaller TD to ESV was associated with a higher intra-LV energy efficiency after PMTA + MVR.

Surgical ventricular reconstruction eligible for late assist device implantation

In patients with ischemic cardiomyopathy and left ventricular aneurysm formation that are symptomatic despite optimal medical therapy it is challenging to determine whether surgical ventricular reconstruction (SVR), heart transplantation, or left ventricular assist device (LVAD) implantation is the treatment of choice. In this report, we present the novel concept of SVR with a specially prepared LVAD fixation ring to facilitate subsequent LVAD implantation if required. In our case endoventricular circular LVAD ring plasty sufficiently reduced the ventricular volume, normalized the left ventricular geometry and subsequently led to an improvement of left ventricular ejection fraction.

Clinical and hemodynamic outcomes of the Dor procedure in adults with ischemic cardiomyopathy

Ischemic cardiomyopathy continues to be a major contributor to congestive heart failure, which places a significant burden on our healthcare system. Improving medications and different coronary revascularization strategies are the mainstays in the management of ischemic cardiomyopathy. Although medications and mechanical circulatory support are playing an ever-increasing role, cardiac transplantation remains the gold standard for treating advanced heart failure. Given the small number of available and suitable donor hearts, transplantation is limited for the majority of patients. Surgical ventricular restoration has repeatedly been suggested as a viable alternative in managing heart failure in select patients, as it is believed that surgically returning the ventricle to its original dimensions is possible and associated with favorable outcomes. The purpose of this manuscript is to comprehensively review the current literature on various surgical strategies for ventricular restoration. We also contextualize the published data with respect to ventricular function, volume, structure, arrhythmias, mitral regurgitation, and clinical outcomes.

Non-heart transplant surgical approaches with mitral valve operation and surgical ventricular reconstruction for non-ischaemic dilated cardiomyopathy: a Japanese multicenter study

OBJECTIVES

There is uncertainty over the efficacy of additional surgical ventricular reconstruction (SVR) associated with mitral valve operation for non-ischaemic dilated cardiomyopathy (DCM). This study aims to assess mid-term outcomes of these non-heart transplant surgical approaches for DCM.

METHODS

We reviewed retrospectively 106 patients (median age 64, 44 females) who underwent isolated mitral annular plasty (MAP; n = 34), mitral valve replacement (MVR; n = 29), and SVR associated with MAP (SVR + MAP; n = 43) for DCM, in 11 Japanese hospitals. We analysed mid-term outcomes, specifically freedom from cardiac death and cardiac event.

RESULTS

Hospital deaths occurred in 16 patients (15.1%) and cardiac deaths in 36 patients (34.0%) during the study period of 4.4 ± 3.5 years. Freedom from cardiac death at 7 years in patients undergoing MAP, MVR, and SVR + MAP were, respectively, 79.1%, 82.6%, and 29.5% (P < 0.0001). Freedom from cardiac event at 7 years in patients undergoing MAP, MVR, and SVR + MAP were, respectively, 42.8%, 59.9%, 22.6% (P = 0.0004). In the multivariable analyses, preoperative tricuspid regurgitation (TR) grade was the only risk factor for both cardiac death and event, whereas MVR for DCM emerged as a protective factor for cardiac event.

CONCLUSIONS

This study could not show any benefit of additional SVR, by means of volume reduction, to MAP, because the baseline characteristics were different even after the stratification of DCM grade. MVR can be performed with favorable mid-term outcomes even in patients with advanced DCM, while patients undergoing MAP with/without SVR had more frequent MR recurrence or cardiac events. Interestingly, the right ventricular feature is a predictor of both cardiac death and events, with the TR grade being a predictor of poor mid-term outcomes.

Autophagy during left ventricular redilation after ventriculoplasty: Insights from a rat model of ischemic cardiomyopathy

OBJECTIVES

Myocardial autophagy has been recognized as an important factor in heart failure. It is not known whether changes in ventricular geometry by left ventriculoplasty influence autophagy in ischemic cardiomyopathy. We hypothesized that myocardial autophagy plays an important role in left ventricular (LV) redilation after ventriculoplasty.

METHODS

Four weeks after ligation of the left anterior descending artery, ventriculoplasty or sham operation was performed. The animals were euthanized at 2 days (early) or 28 days (late) after the second operation. Ventricular autophagy was evaluated by protein expression of microtubule-associated protein light chain 3 II, an autophagosome marker. Cardiomyocyte area was assessed by histologic examination. LV function was evaluated by echocardiography. To examine the implications of autophagy, an autophagy inhibitor (3-methyladenine) was injected intraperitoneally for 3 weeks before sacrifice.

RESULTS

The LV was reduced in size early and redilated late after ventriculoplasty. LV systolic function was improved early and later worsened after ventriculoplasty. Light chain 3 II expression decreased early after ventriculoplasty and increased in the late period. Myocyte area increased from the early to late stage after ventriculoplasty. Autophagic inhibition exaggerated the increased myocyte hypertrophy and LV redilation.

CONCLUSIONS

In a rat model of myocardial infarction, autophagy decreased early after ventriculoplasty and increased again during LV redilation. These results provide new insights into the mechanism underlying the late failure of ventriculoplasty.