A Retrospective Observational Study of Patients with Dilated Cardiomyopathy Undergoing Non-Cardiac Surgery

The perioperative risks and factors associated with adverse cardiac outcomes in patients with dilated cardiomyopathy undergoing non-cardiac surgery are unknown. Interrogation of the Nelson Hospital transthoracic echocardiogram database identified 127 patients with dilated cardiomyopathy who satisfied the study criteria and underwent non-cardiac surgery between June 1999 and July 2013. Demographic and clinical data along with postoperative death within 30 days or a major adverse cardiac event were retrieved and analysed. The mean age was 75.9 years. Seventy-one percent of the patients had severe impairment of left ventricular function and 35% had a severely dilated left ventricle. A major adverse cardiac event occurred in 18.1% of patients and 5.5% of patients died within 30 days of surgery. Increased surgical risk and absence of cerebrovascular disease were associated with adverse outcome (P <0.001, P <0.05, respectively). Forty-three and a half percent (43.5%) of patients undergoing high-risk surgery had an adverse outcome compared to 36.1% and 5.9% for moderate and low-risk surgery, respectively. A major adverse cardiac event was observed in 26.7% of patients with cardiovascular disease compared to 9.8% of patients without cardiovascular disease. We were unable to exclude an influence of other potential risk factors due to the retrospective observational nature of the study. These findings highlight a potential increase in complications with moderate or high surgical risk, whilst are reassuring in demonstrating the relative safety of low-risk surgery in this group of high-risk patients.