The Left Ventricular Mass Regression Paradox following Surgical Valve Replacement: A Real Phenomenon or a Mathematical Glitch?

Left Ventricle Mass Regression After Surgical or Transcatheter Aortic Valve Replacement in Veterans

BACKGROUND

Differences in left ventricular mass regression (LVMR) between transcatheter aortic valve replacement (TAVR) and surgical aortic valve replacement (SAVR) have not been studied. We present clinical and echocardiographic data from veterans who underwent TAVR and SAVR, evaluating the degree of LVMR and its association with survival.

METHODS

We retrospectively reviewed TAVR (n = 194) and SAVR (n = 365) procedures performed in veterans from 2011 to 2019. After 1:1 propensity matching, we evaluated mortality and secondary outcomes. Echocardiographic data (median follow-up 957 days, interquartile range 483-1652 days) were used to evaluate LVMR, its association with survival, and predictors of LVMR.

RESULTS

There was no difference between SAVR and TAVR patients in mortality (for up to 8 years), stroke at 30 days, myocardial infarction, renal failure, prolonged ventilation, reoperation, or structural valve deterioration. SAVR patients (67.3% [101 of 150]) were more likely to have LVMR than TAVR patients (55.7% [44 of 79], P = .11). The magnitude of LVMR was greater for the SAVR patients (median, -23.3%) than for the TAVR patients (median, -17.8%, P = .062). SAVR patients with LVMR had a survival advantage over SAVR patients without LVMR (P = .016). However, LVMR was not associated with greater survival in TAVR patients (P = .248).

CONCLUSIONS

SAVR patients were more likely to have LVMR and had a greater magnitude of LVMR than TAVR patients. LVMR was associated with better survival in SAVR patients, but not in TAVR patients.

Comparison of cardiac energetics after transcatheter and surgical aortic valve replacements

OBJECTIVES

The effect of transcatheter aortic valve replacement (TAVR) on cardiac energetics has not been described. We compared changes in cardiac energetics after TAVR with those after surgical aortic valve replacement (SAVR).

METHODS

We retrospectively estimated end-systolic elastance (Ees) and effective arterial elastance (Ea) using blood pressure and left ventricular (LV) volume obtained from echocardiography. LV efficiency [ventriculoarterial coupling (Ea/Ees) and the stroke work to pressure-volume area ratio (SW/PVA)] was calculated. Measurements were taken before, 1 week after and 1 year after bioprosthetic aortic valve replacement (TAVR, n = 56; SAVR, n = 61) in patients with severe aortic stenosis and preserved ejection fraction.

RESULTS

Patients with TAVR had a lower aortic valve pressure gradient and larger stroke volume 1 week after the procedure than those with SAVR. Ea was more markedly decreased, and LV efficiency was significantly improved 1 week after TAVR (SW/PVA 68.1% ± 8.4% to 72.0% ± 8.5%, P < 0.001), but LV efficiency was unchanged 1 week after SAVR (SW/PVA 70.1% ± 7.4% to 69.1%  ±  8.0%). LV efficiency was improved 1 year after both procedures (SW/PVA 75.5% ± 6.1% in TAVR; 74.7% ± 6.4% in SAVR).

CONCLUSIONS

TAVR decreases the transvalvular pressure gradient further without deteriorating stroke volume in the early postoperative period, which is accompanied by early improvement in afterload and LV efficiency compared with SAVR. Improvement in LV efficiency at mid-term follow-up is satisfactory after both procedures.

Impact of Metabolic Syndrome and/or Diabetes Mellitus on Left Ventricular Mass and Remodeling in Patients With Aortic Stenosis Before and After Aortic Valve Replacement

In aortic stenosis (AS), metabolic syndrome (MetS), and diabetes mellitus (DM) are associated with more pronounced left ventricular (LV) hypertrophy and more concentric remodeling. We aimed to assess the impact of MetS and DM on LV mass, remodeling, and LV mass regression after aortic valve replacement (AVR) in patients with severe AS. We included 177 patients with severe AS and preserved LV ejection fraction (>50%). All patients underwent a complete echocardiogram before and 1 year after AVR. Forty-seven (27%) patients had MetS, 37 (21%) DM, and 93 (52%) neither MetS nor DM (No MetS-DM). Before AVR, indexed LV mass was higher in MetS and DM groups compared with No MetS-DM group (56.1 ± 14.2, 56.2 ± 18.2 vs 49.2 ± 14.1 g/m^2.7, respectively; p <0.01). Prevalence of LV hypertrophy was higher in MetS and DM than in No MetS-DM patients (66%, 65% vs 44%, p <0.01) as well as LV mass to end-diastolic volume ratio (2.10 ± 0.44 and 2.21 ± 0.63 vs 1.96 ± 0.41 g/ml, respectively, p = 0.03). After multivariate analysis, DM and MetS were independently associated with higher baseline LV mass (p <0.05). One year after AVR, decrease in LV mass was significant (p <0.001) in all 3 groups. MetS was independently associated with less LV mass regression and higher LV mass 1 year after AVR. Therefore, MetS and DM patients showed more residual LV hypertrophy than those with No MetS-DM (57%, 38%, and 17%, p <0.01). In conclusion, MetS and DM were associated with higher preoperative LV mass, more LV hypertrophy, and more concentric remodeling. One year after AVR, MetS showed less significant LV mass regression and both DM and MetS persisted with more residual LV hypertrophy.