Fernando Santos
Anesthesiologist
Los Robles Hospital and Medical Center
Thousand Oaks, California
Disclosure information not submitted.
Phat Dang
Doctor of Medicine
University of California Irvine, United States
Disclosure information not submitted.
Title: LAD Occlusion Causing Refractory Postoperative Ventricular Tachycardia After LVAD Implantation
Case Report Body:
Introduction: Ventricular tachyarrhythmias (VT) is a known complication after left ventricular assist device (LVAD) placement that is rarely caused by left anterior descending artery (LAD) occlusion.
Description: A 73-year-old male with ischemic cardiomyopathy status post 3-vessel coronary bypass presented with worsening fatigue and dyspnea on exertion. Echocardiography findings were consistent with Stage D heart failure and moderate right ventricular (RV) dysfunction. Cardiac catheterization showed multivessel disease not amenable to revascularization so he underwent minimally invasive LVAD implantation. Post-LVAD, he experienced refractory monomorphic VT, suspected to be caused by a large myocardial scar from prior infarction. He was not an ablation candidate due to hemodynamic instability during VT episodes. Despite periods of electrical quiescence and multiple interventions, his VT persisted for over 8 weeks. After careful discussion of risks due to preexisting kidney injury and RV dysfunction, cardiac catheterization revealed 100% ostial and mid LAD occlusion, requiring drug eluting stent (DES) placement. This greatly improved his VT but he unfortunately went into acute renal failure. This led to fluid overload, RV failure, multiorgan failure, and eventual death.
Discussion: Early VT is common post-LVAD and associated with increased 30-day all-cause mortality. The presence of pre-LVAD VT is a strong predictor of post-LVAD VT. Ischemic cardiomyopathy as the cause of heart failure has not been demonstrated to be a negative nor positive predictor. Evaluation of post-LVAD VT should include EKG, laboratory studies, echocardiogram, and LVAD interrogation. Medical management includes correction of known triggers, and antiarrhythmic therapy. Ablation can be considered in refractory cases but this wasn’t an option in this case. LAD occlusion is a rare cause of VT in post-LVAD patients and several aspects of this case made the diagnosis challenging. He had few risk factors associated with post-LVAD VT, his VT episodes were not always preceded by scenarios that might cause ischemia, and the monomorphic nature of his VT suggested that the etiology was a pre-existing scar. This case demonstrates that coronary occlusion should always be considered in the immediate post-LVAD period as a reversible cause of VT.