Microvascular autonomic dysfunction may justfy false-positive stress myocardial perfusion imaging in patients with liver cirrhosis undergoing liver transplantation.

Abstract: Background. Up to 15% of liver transplant candidates have asymptomatic coronary artery diseases, which increase the risk of cardiac complications during and after transplantation. The aim of this study was to prospectively investigate the usefulness of an integrated cardiological approach in cirrhotic patients undergoing liver transplantation. Methods. Twenty-four consecutive patients undergoing evaluation for liver transplantation were studied by assessing risk factors for coronary artery diseases, electrocardiogram with QTc interval determination, chest X-ray, echocardiography, 24-hour Holter monitor, myocardial perfusion scintigraphy 99-TcMIBI-GSPECT at rest and after dipyridamole infusion. Cardiac I-123-metaiodobenzylguanidine (MIBG) scan and coronarography were performed in patients with myocardial perfusion defects. Twenty three of 24 patients underwent successful liver transplantation; one patient died on the waiting list. Results. Before liver transplantation, 29% of patients were diabetic and 41% were smokers. Eleven of 24 patients had a prolonged QTc interval, and 3/24 had positive myocardioscintigraphy after dipyridamole infusion: in two coronarography was negative, while the I-123-MIBG washout was altered. No cardiac events were recorded during the short-and long-term follow-up after surgery. Conclusions. Predictive value of positive cardiac (MIBI)-M-99Tc-GSPECT in patients with liver cirrhosis is low, and this may be due to alterations of cardiac microvascular tone as showed by cardiac I-123-MIBG scan.