CHICAGO (May 24, 2010) –Symptomatic heart failure prior to surgery is routinely acknowledged as a risk factor for adverse outcomes for both cardiac and non-cardiac surgeries. In a new study published in the June Anesthesiology, researchers delve further into the implications of cardiac problems on postoperative outcomes, exploring preoperative diagnosis and impact of asymptomatic left ventricular (LV) dysfunction in vascular surgery patients.
Asymtomatic LV dysfunction is considered a precursor to symptomatic heart failure, a condition researchers from the Department of Anesthesiology at Erasmus Medical Center in Rotterdam, The Netherlands, recognize as a well established risk factor for postoperative cardiac events.
“We conducted the present study to evaluate the impact of asymptomatic systolic and/or diastolic LV dysfunction on outcomes following surgery,” said study investigator Don Poldermans, M.D., Ph.D. of the Department of Anesthesiology at Erasmus Medical Center. “LV dysfunction is frequently present, and mostly asymptomatic. If it is proven that asymptomatic dysfunction is involved in adverse cardiac outcomes, proper perioperative care and therapy can be initiated to prevent worsening of heart failure during surgery.”
About the Study
LV dysfunction was diagnosed through echocardiography performed preoperatively on 1,005 consecutive vascular surgery patients. LV dysfunction was diagnosed in 506 of the patients evaluated. Of these diagnosed patients, 80 percent of the cases were asymptomatic.
LV dysfunction diagnoses were evaluated to be either systolic and/or diastolic LV dysfunction. If LV dysfunction was present in combination with heart failure symptoms of shortness of breath, fatigue, exercise intolerance or signs of fluid retention, patients were diagnosed with symptomatic heart failure.
All patients underwent open vascular surgery or minimally invasive endovascular surgery and were evaluated for cardiovascular events for 30 days following surgery and for long-term cardiovascular related death. Cardiovascular events included myocardial ischemia, myocardial infarction, and cardiovascular event-related death.
Outcomes and Next Steps
In open vascular surgery, both asymptomatic systolic and isolated diastolic LV dysfunction was associated with cardiovascular events occurring within 30 days following surgery and long-term cardiovascular-related death. For patients treated through endovascular surgery, only patients diagnosed with symptomatic heart failure before surgery were associated with 30-day cardiovascular events and long-term cardiovascular related death.
Study results established the need to evaluate all possible cardiovascular risk factors for high-risk vascular surgery patients.
“This study demonstrated that asymptomatic LV dysfunction is indeed predictive for adverse 30-day and long-term cardiovascular outcomes in open vascular surgery patients,” said Dr. Poldermans. “The data suggest that routine assessment for asymptomatic left ventricular dysfunction prior to vascular surgery improves preoperative risk stratification.”
Dr. Poldermans and colleagues conclude that perioperative care therapy such as beta-blockers can be an effective treatment to improve postoperative outcomes. Dr. Poldermans recommends that if asymptomatic heart failure is present and beta-blocker therapy is considered, a carefully titrated dosing regimen be implemented in these patients.
An accompanying editorial by Leanne Groban, M.D. and Dalane W. Kitzman, M.D., of the Departments of Anesthesiology and Internal Medicine, Section on Cardiology, Sticht Center of Aging, Wake Forest School of Medicine in Winston-Salem, North Carolina, discusses clinical implications of the study results, predicting that preclinical detection of LV dysfunction will improve risk estimates and enable for better management of therapy around the time of surgery to decrease the occurrence of cardiovascular events. The authors summarized that therapy strategies could include optimization of preoperative cardiac medications, enhanced monitoring, specialized fluid management strategies or more intensive postoperative surveillance.