Renal transplant recipients are at higher risk for development of valvular heart disease, including mitral regurgitation. The management of severe mitral regurgitation among renal transplant recipients poses a challenging dilemma. Renal transplant recipients have high postoperative risk with surgical mitral valve replacement, owing to their multiple comorbidities, immunosuppressed state and prior multiple surgeries. Transcatheter Edge to Edge Repair (TEER) with MitraClip (Abbott Structural, Menlo Park, CA) is currently approved for patients with severe symptomatic primary mitral regurgitation at high risk for surgery, as well as patients with moderate-to-severe or severe symptomatic secondary mitral regurgitation on optimal guideline-directed medical therapy. , Interest has been directed to exploring the outcomes of TEER among the high-risk group of patients with prior renal transplant. Hence, we aimed to evaluate the outcomes of TEER among this group of patients using a large claim database.
The National Readmissions Database (2014 to 2018) was used to identify hospitalizations for TEER using International Classification of Diseases, Ninth and Tenth editions (ICD-9 and ICD-10) procedure codes “35.97 and 02UG3JZ.” Renal transplant recipients were identified using ICD-9 and ICD-10 diagnostic codes “V42.0 and Z94.0.” The study was designed to compare in-hospital mortality among renal transplant recipients versus patients who have not had transplants. Multivariable regression analysis was conducted to adjust for clinical variables that were significant on univariable analysis. This study was exempt from institutional review board evaluation, since data from the NRD are publicly available and devoid of personal identifiers. All statistical analyses were conducted using the SPSS software (IBM SPSS Statistics for Windows, Version 25.0. Armonk, NY: IBM Corp Released 2017).
Among 23,835 hospitalizations for TEER, 134 hospitalizations were among renal transplant recipients. number of renal transplant recipients undergoing TEER increased during the study years (12 in 2014 vs 53 in 2018, p trend <0.001). Compared with nontransplant recipients, renal transplant recipients undergoing TEER were younger (67.9 ± 11.7 vs 77.6 ± 10.8 years, p = 0.80), with similar female representation (44% vs 46.6%, p = 0.68), and similar prevalence of diabetes, chronic liver disease, peripheral vascular disease, prior myocardial infarction, prior stroke, prior coronary artery bypass grafting, chronic dialysis, and obesity. Renal transplant recipients were more likely to have chronic systolic heart failure (57.5% vs 42.5%, p <0.001) and less likely to have chronic lung disease (14.2% vs 27.9%, p <0.001). TEER was performed among patients presenting with cardiogenic shock similarly across both groups (1.5% vs 0.8%, p = 0.67).
The crude in-hospital mortality was higher among renal transplant recipients versus nontransplant recipients (14.2% vs 2.4%, odds ratio (OR) 6.53; 95% confidence interval (CI) 4.28 to 9.96, p <0.001). Similar findings were observed after multivariable adjustment (adjusted-OR 6.55; 95% CI 4.15 to 10.34, p <0.001). On multivariable analysis, there were no differences between both groups in the rates of cardiac arrest, cardiogenic shock, mechanical circulatory support, acute kidney injury, requirement of hemodialysis, acute MI, acute stroke, major bleeding, cardiac tamponade/hemopericardium, ventricular arrhythmias, complete heart block, pacemaker implantation and discharges to nursing facilities. Renal transplant recipients were associated with higher rates of respiratory tract infections (adjusted-OR 4.19; 95% CI 2.75 to 6.39), urinary tract infections (adjusted-OR 2.27; 95% CI 1.69 to 3.06) and prolonged mechanical ventilation (>96 hours) (adjusted-OR 4.41; 95% CI 3.31 to 6.20). Adjusted analysis showed no difference among both groups in the rates of 30-day nonelective readmissions (27.6% vs 23.8% adjusted-OR 1.31; 95% CI 0.58 to 2.96, p <0.001; Figure 1 ).
