Site-Level Variability in 30-Day Patient Outcomes After Transcatheter Mitral Valve Repair in the United States

Background: Clinical trials have demonstrated health status benefit of transcatheter mitral valve repair (TMVr) with MitraClip in patients with mitral valve regurgitation. Real-world site-level variability in health status outcomes for TMVr, and factors associated with this variability, are unknown. Methods: All patients undergoing TMVr procedure with MitraClip between November 2013 and March 2019 in the Transcatheter Valve Therapy Registry were included. Health status was measured at baseline and 30 days with the Kansas City Cardiomyopathy Questionnaire (KCCQ) Overall Summary (OS) score. Site-level variability in 30-day change in KCCQ-OS was examined by calculating the median odds ratio from a hierarchical logistic regression model, with ≥20-point improvement as the dependent variable. To define the extent to which patient characteristics, procedural characteristics (residual mitral valve regurgitation, periprocedural bleeding), site volume, and patients’ baseline health status accounted for variability in outcomes, the proportion of variability ( R 2 ) explained by sequentially adding these variables to the model was quantified. Results: Across 339 sites, 12 415 patients (mean age 79.0±9.5 years, 46.1%. females, 89.5% White) completed baseline and 30-day health status assessments. Mean KCCQ-OS score was 43.0±24.4 at baseline and 67.0±24.9 at 30-day follow-up. Across sites, the proportion of patients achieving a ≥20-point improvement in KCCQ-OS ranged from 12.5% to 100% and the adjusted median odds ratio was 1.58 (95% CI, 1.46–1.69). The greatest contribution to the variability in health status outcomes was from patients’ baseline KCCQ-OS score ( R 2 =25%) with <1% of the variability explained by patient and procedural characteristics, and annual site volume. Conclusions: There is moderate variation across sites in their patients’ achievement of health status benefits from TMVr, with patient’s baseline health status accounting for the largest proportion of this variation. This underscores the importance of patient selection in supporting more consistent health status benefit from TMVr.

Abstract 104: The Effect of Low Perceived Social Support on Health Outcomes in Young Patients with Acute Myocardial Infarction: Results from the VIRGO Study

Background: Social support is an important predictor of health outcomes after acute myocardial infarction (AMI), but significant variability in social support exists by sex and age. Most studies have been conducted in populations of predominately older, male patients; little is known about the impact of social support on outcomes after AMI in young patients, who may have unique demands and resources. Methods: We used data from the VIRGO study, an observational study of patients aged ≤55 years with AMI in the US and Spain, to examine the association of low perceived social support (LPSS) with baseline and 1-year health status, depression, and quality of life. Patients were categorized as having low vs. moderate/high social support using the ENRICHD Social Support Inventory (ESSI), which was collected during the index AMI hospitalization. A modified 5-item version of the 7-item ESSI was used for this study in order to examine marital status and instrumental support separately from perceived social support. Outcomes included health status (assessed by the Short Form-12 (SF-12) physical and mental component scores (PCS and MCS)), depressive symptoms (Patient Health Questionnaire (PHQ-9)), and angina-related quality of life (Seattle Angina Questionnaire (SAQ)) evaluated at baseline and 1-year. We used linear regression to compare 1-year health status between social support categories, adjusting for baseline health status, socio-demographics, comorbidities, severity of disease, and therapies used. Results: Among 3,432 patients, 728 (21.2%) were classified as having LPSS. Men and women had comparable levels of social support at baseline. On average, patients with LPSS reported lower functional status (PCS and MCS), lower quality of life, and more depressive symptoms at baseline and 1-year post-AMI. After multivariable adjustment, including baseline health status, LPSS was associated with lower mental functioning (mean MCS -2.34 (95% confidence interval [CI] -3.35, -1.34) p<0.001), lower quality of life (mean SAQ -4.58 (95% CI -4.58, -2.57), p<0.001), and more depressive symptoms (1.01 (95% CI 0.52, 1.51), p<0.001) at 1 year. The relationship between LPSS and worse physical functioning was not significant after adjustment (mean PCS -0.28 (95% CI -1.33, 0.77), p=0.6). We observed no interactions between social support, sex or country. Conclusion: Lower social support is associated with worse health status and more depressive symptoms 1-year after AMI in both young men and women recovering from an AMI.

Abstract 194: Pre-Operative Health Status is Only Weakly Associated With Mortality or Hospitalization Following Continuous-Flow Left Ventricular Assist Device Implantation

Background: Health status predicts death and hospitalization in heart failure and cardiac surgery, but its prognostic value in the setting of left ventricular assist device (LVAD) placement is unknown. We hypothesized that baseline health status could help identify patients at risk for adverse post-operative outcomes and improve patient selection for LVAD therapy. Methods: We examined the association of pre-operative health status, as measured by the Kansas City Cardiomyopathy Questionnaire (KCCQ) overall summary score (OSS), with overall mortality and hospitalization in 965 patients undergoing LVAD placement as part of two clinical trials of the HeartMate II device. Unadjusted statistical analyses were performed using Cox proportional hazard models and Kruskal-Wallis non-parametric tests. Results: Baseline OSS of survivors (median: 25.5, inter quartile range (IQR): 15.6-38.6) was similar to those who died (median: 23.4, IQR 12.9-39.2, p=0.06). Patients in the lowest quartile of KCCQ scores (OSS<14.8) had worse survival as compared with the upper 3 quartiles (unadjusted HR: 1.30. 95% CI 1.03-1.63, p=0.03). Patients in the lowest quartile of baseline OSS also spent more time in the hospital (median 25 days, IQR 19-42) as compared with the upper 3 quartiles (median 23 days, IQR 17-35, p=0.009). Outcomes for the 3 higher OSS quartiles were not significantly different. When comparing KCCQ sub-domain scores of patients who died during follow-up to those who did not, lower total symptom score was significantly associated with worse survival (p=0.009); all other KCCQ sub-domains were not. Conclusion: Only patients with very low baseline health status (KCCQ <15) were at increased risk for mortality and hospitalization following LVAD implantation, with the absolute differences being very small. This weak association between baseline KCCQ and post-operative outcomes suggests that LVAD implantation, unlike chronic heart failure and other cardiac surgeries, represents a unique clinical situation in which the benefits of the intervention may outweigh the anticipated risks of worse health status.