Cardiac Resynchronization Therapy In A Patient With Cardiac Allograft Vasculopathy

Abstract

Background Reports describing cardiac resynchronization therapy (CRT) in patients with a cardiac allograft are limited to 2 cases in the setting of a new left bundle branch block. A case of CRT use and response in cardiac allograft vasculopathy (CAV) has not occurred to date. Objective Describe the use of CRT in a patient who developed CAV with right bundle branch block/left anterior fascicular block 5 years after orthotopic heart transplant (OHT). Methods N/A Results A 44-year old male with a history of non-ischemic cardiomyopathy, implantable defibrillator (ICD), and polycystic kidney disease received a dual heart and kidney transplant in May 2015. Annual right heart catheterization in May 2020 showed elevated biventricular filling pressures and cardiac index of 2 L/min/m2. Left heart catheterization showed early CAV. Endomyocardial biopsy results were negative for cellular or antibody-mediated rejection, and infiltrative/inflammatory processes. A transthoracic echocardiogram (ECHO) was significant for a depressed ejection fraction (25%), severe left ventricular global hypokinesis, and moderate to severe right ventricular dysfunction. Despite guideline-directed medical therapy consisting of sacubitril-valsartan, carvedilol, and spironolactone, cardiac function did not change on repeat ECHO. EP consultation noted the progression of ECG changes from a baseline narrow QRS complex post-OHT, to right bundle branch block (QRS 122 ms) January 2019, and right bundle branch block with left anterior fasicular block (QRS 150 ms) September 2020. A CRT-ICD was subsequently implanted. Biventricular pacing was initially set to no interventricular delay. An ECHO 3 months later showed significant improvement in cardiac function with a “mildly depressed” EF (42%), anterior/inferior dyskinesis, normalization of left ventricular end-diastolic dimension (4.8 cm from 5.5 cm), and right ventricular function. Electrocardiographic optimization changed the paced QRS width from 180 ms to 154 ms when left ventricular pacing was programmed 50 ms early, and minimized dyskinesis. Conclusion Response to CRT in OHT patients developing CAV cardiomyopathy with significant ventricular conduction delay can occur, and should be considered before more advanced heart failure therapies are applied. Reports describing cardiac resynchronization therapy (CRT) in patients with a cardiac allograft are limited to 2 cases in the setting of a new left bundle branch block. A case of CRT use and response in cardiac allograft vasculopathy (CAV) has not occurred to date. Describe the use of CRT in a patient who developed CAV with right bundle branch block/left anterior fascicular block 5 years after orthotopic heart transplant (OHT). N/A A 44-year old male with a history of non-ischemic cardiomyopathy, implantable defibrillator (ICD), and polycystic kidney disease received a dual heart and kidney transplant in May 2015. Annual right heart catheterization in May 2020 showed elevated biventricular filling pressures and cardiac index of 2 L/min/m2. Left heart catheterization showed early CAV. Endomyocardial biopsy results were negative for cellular or antibody-mediated rejection, and infiltrative/inflammatory processes. A transthoracic echocardiogram (ECHO) was significant for a depressed ejection fraction (25%), severe left ventricular global hypokinesis, and moderate to severe right ventricular dysfunction. Despite guideline-directed medical therapy consisting of sacubitril-valsartan, carvedilol, and spironolactone, cardiac function did not change on repeat ECHO. EP consultation noted the progression of ECG changes from a baseline narrow QRS complex post-OHT, to right bundle branch block (QRS 122 ms) January 2019, and right bundle branch block with left anterior fasicular block (QRS 150 ms) September 2020. A CRT-ICD was subsequently implanted. Biventricular pacing was initially set to no interventricular delay. An ECHO 3 months later showed significant improvement in cardiac function with a “mildly depressed” EF (42%), anterior/inferior dyskinesis, normalization of left ventricular end-diastolic dimension (4.8 cm from 5.5 cm), and right ventricular function. Electrocardiographic optimization changed the paced QRS width from 180 ms to 154 ms when left ventricular pacing was programmed 50 ms early, and minimized dyskinesis. Response to CRT in OHT patients developing CAV cardiomyopathy with significant ventricular conduction delay can occur, and should be considered before more advanced heart failure therapies are applied.