Angiotensin converting enzyme inhibitor therapy in severe postcardiotomy dysfunction: a prospective randomized study

Cardioprotective Strategies to Improve Long-Term Outcomes Following Coronary Artery Bypass Surgery

BACKGROUND AND AIM

Cardioprotective strategies implemented to prevent ischemic events in patients at risk for cardiovascular disease have decreased morbidity and prolonged survival. In this review, we have used evidence-based medicine and number-needed-to-treat (NNT) analyses to determine which interventions are most beneficial in minimizing ischemic events and prolonging survival following coronary artery bypass graft (CABG) surgery.

METHODS

Therapeutic interventions available to minimize ischemic events in the post-CABG patient were analyzed using ACC/AHA Classifications and Level of Evidence Criteria. Based on these recommendations, NNT analyses were performed to determine the effectiveness of each intervention compared to the number of patients needed to be treated before a benefit was apparent.

RESULTS

The most beneficial intervention to improve mortality following CABG was the use of high tissue angiotensin-converting enzyme inhibitors, followed by statins and smoking cessation.

CONCLUSIONS

NNT analyses and evidence-based medicine recommendations provide surgeons with cardioprotective strategies to improve long-term outcomes following CABG surgery.

Role of Angiotensin-Converting Enzyme Inhibitors in the Coronary Artery Bypass Patient

Angiotensin-converting enzyme inhibitors have been shown to prolong survival and decrease infarct size in patients after acute coronary syndromes. Now there is evidence to suggest that angiotensin-converting enzyme inhibition is beneficial in coronary artery bypass patients. This review will summarize the beneficial effects of angiotensin-converting enzyme inhibition in patients with ischemic heart disease and provide evidence to show that the routine use of angiotensin-converting enzyme inhibition in coronary artery bypass patients can improve clinical outcomes.

The use of angiotensin-converting enzyme inhibitors in patients undergoing coronary artery bypass graft surgery

Angiotensin-converting enzyme inhibitors have been shown to prolong survival, decrease infarct size, and improve ventricular function in patients who have congestive heart failure, and in those who have sustained a myocardial infarction. This review will summarize the evidence to show that angiotensin-converting enzyme inhibitors can also benefit patients undergoing coronary artery bypass graft surgery by minimizing perioperative ischemia, and reducing long-term cardiovascular events.

Microvascular alterations in patients with acute severe heart failure and cardiogenic shock

BACKGROUND

Microvascular blood flow alterations may impair tissue oxygenation and may participate in the development of multiple organ failure in patients with severe heart failure. We hypothesized that microvascular blood flow alterations are present in patients with severe heart failure and cardiogenic shock.

METHODS

We used an orthogonal polarization spectral imaging technique to investigate the sublingual microcirculation in 40 patients with acute severe heart failure, including 31 patients with cardiogenic shock, and in a control group of 15 patients who were examined the day before cardiac surgery. The effects of topical application of acetylcholine (10-2M) were also tested in 5 patients with cardiogenic shock. Five sublingual areas were recorded, allocated a random number, and later analyzed semiquantitatively. Data were analyzed with non-parametric tests and presented as medians (percentiles 25-75).

RESULTS

The density of all the vessels was similar in the 3 groups. The proportion of perfused small (<20 microm) vessels was lower in patients with cardiac failure and cardiogenic shock than in control patients (63% [46%-65%] and 49% [38%-64%] vs 92% [90%-93%], P <.001). The perfusion of large vessels was preserved in all groups. The proportion of perfused vessels was higher in patients who survived than in patients who did not survive in all vessels (90% [84%-93%] vs 81% [74%-87%], P <.05) and in small vessels (64% [49%-68%] vs 43% [37%-62%], P <.05). The topical application of acetylcholine totally reversed these alterations

CONCLUSIONS

Microvascular blood flow alterations are frequently observed in patients with severe heart failure and are more severe in patients who do not survive.

Management of perioperative ventricular dysfunction

With the recognition of the clinical importance of the right ventricle; the development of new techniques for the perioperative evaluation of RV function, particularly transesophageal echocardiography; and new treatment modalities (pharmacologic and mechanical), clinicians will be able to more accurately diagnose and precisely manage patients who have sustained RV injury.