Cardiology

We evaluated the prognostic value of cardiac magnetic resonance (CMR) stress testing with direct comparison of adenosine stress first-pass perfusion and dobutamine stress wall motion imaging among 513 subjects with known or suspected coronary heart disease over a median follow-up period of 2.3 years. Positive results on CMR stress testing identified subjects at high risk for subsequent cardiac events (nonfatal myocardial infarction or cardiac death), whereas normal CMR stress test results were associated with a very low annual cardiac event rate.

In Jahnke et al's study, the authors showed the prognostic value of yet another imaging modality—perfusion magnetic resonance (MR) imaging and dobutamine stress MR.

We conducted a substudy of the Rate Control Versus Electrical Cardioversion (RACE) study to evaluate cardiovascular morbidity, mortality, and the outcome of rate and rhythm control treatment in subjects with and without hypertension with persistent atrial fibrillation.

This review summarizes an important substudy of the Rate Control Versus Electrical Cardioversion (RACE) trial, which randomized 522 patients with atrial fibrillation (AF) to rate versus rhythm control treatment strategies and followed them for up to 2.3 years with a primary composite endpoint that included cardiovascular mortality, heart failure, thromboembolic complications, bleeding, severe adverse effects of anti-arrhythmic agents, and pacemaker implantation.

The use of anticoagulation therapy for atrial fibrillation has slowly increased in the last decade, yet many patients at relatively high risk for thromboembolic events are still not receiving anticoagulants. Patients receiving therapy that is intended to maintain sinus rhythm may be at higher risk for underuse of anticoagulation therapy than those receiving rate control therapies. In addition, the increase in the use of anticoagulation therapy appears to have been particularly notable among patients for whom it may not be indicated and in whom safer, less expensive antithrombotic therapies would suffice.

Atrial fibrillation (AF) is the most common clinical arrhythmia and is of enormous importance for public health in view of its significant mortality and morbidity.

We evaluated more than 26 000 subjects from 4 large trials that included subjects with non–ST-segment elevation acute coronary syndromes to determine the prognostic importance of creatine kinase-myocardial band (CK-MB) elevation after coronary artery bypass graft (CABG) surgery during the index hospitalization. Results showed that mortality at 6 months increased with increasing peak CK-MB ratios (CK-MB value post-CABG/CK-MB upper limit of normal), and peak CK-MB ratio was an independent predictor of 6-month outcome.

In their study consisting of coronary artery bypass graft (CABG) patients recruited from 4 major trials, Mahaffey found that creatine kinase-myocardial band (CK-MB) elevations following CABG surgery are independently associated with an increased risk of mortality in patients with non–ST-segment elevation acute coronary syndromes, especially if the peak CK-MB level is > 5 x the upper limit of normal (ULN).

There is scant systematic literature available on acute aortic occlusion. A review of 46 cases in a single center found 2 primary causes, including embolism (65%) or thrombosis (35%).1 Smoking and diabetes were found to be the risk factors for thrombotic occlusion and pre-existing cardiac disease and female gender risk factors for embolism. Acute aortic occlusion due to embolization of a large thrombus from left atrial appendage occurred in a patient with atrial fibrillation at our institution recently (Radha Sharma,MD, personal communication, February 2008). Case reports have described embolization of atrial myxoma to the abdominal aorta resulting in aortoiliac occlusion.2,3

In a secondary post-hoc analysis of the Reduction of Restenosis in Saphenous Vein Grafts with Cypher (RRISC) trial, we compared the long-term safety of sirolimus-eluting stents (SES) with bare-metal stents (BMS) in diseased saphenous vein grafts

Progressive disease in saphenous vein grafts remains a major short-term and long-term clinical challenge after surgical revascularization.

We conducted a prospective, double-blind, randomized, multicenter study among 241 patients who underwent their first on-pump coronary artery bypass graft (CABG) surgery, aortic valve replacement (AVR), or combined CABG and AVR surgery to determine whether the use of hydrocortisone prevents atrial fibrillation after cardiac surgery. Results showed that the incidence of postoperative atrial fibrillation was significantly lower in the hydrocortisone group compared with the placebo group.

Atrial fibrillation (AF) is common after cardiac surgery, occurring in 11% to 40% of patients after coronary artery bypass grafting (CABG)1-8 and in more than 50% of patients after valvular heart surgery.

Triglyceride levels are usually measured after the patient has fasted, and then exclude remnant lipoproteins. Except for the first few hours of the morning, individuals are usually in a nonfasting state for most of the day. We investigated whether nonfasting triglyceride levels predicted the risk of myocardial infarction (MI), ischemic heart disease, and death in the general population. Results showed that increased nonfasting triglyceride levels were associated with an increased risk of MI, ischemic heart disease, and death.

Cardiac troponin T (cTnT) and B-type natriuretic peptide (BNP) have been used to estimate prognosis in heart failure. However, most studies have evaluated decompensated patients using single measurements. To determine the value of serial measurements, we evaluated 190 stable chronic heart failure patients every 3 months during 2 years.

Assessing prognosis in heart failure poses a challenge in clinical practice.

We conducted a study among 15 714 Dutch middle-aged women consuming modest-glycemic-load diets. Results showed that high dietary glycemic load and glycemic index increased the risk of cardiovascular disease. This association was particularly evident among overweight women. Recommendations to follow a high-carbohydrate diet may therefore not be optimal in the prevention of cardiovascular diseases.

Ruptured or vulnerable plaques exist not only at the culprit lesion but also in the whole coronary artery in some acute coronary syndrome (ACS) patients.Goldstein et al found features of instability of nonculprit plaques in nearly 40% of patients by angiography,1 whereas actual rupture in a remote site other than the angiographic culprit lesion was found in approximately 13% to 79% of cases when evaluated by intravascular ultrasound.

What is glycemic load and why is it important?

We evaluated a multiethnic cohort of subjects with nonrheumatic atrial fibrillation hospitalized over a 6-year period to determine the racial and ethnic differences in the risk of intracranial hemorrhage (ICH) and the effect of warfarin treatment on ICH risk. Treatment with warfarin was associated with a 2-fold greater risk of ICH in whites, a 4- to 5-fold greater risk in both blacks and Hispanics, and a 15-fold greater risk in Asians. After adjusting for established stroke risk factors and warfarin use, Asians were 4 times as likely as whites to have ICH, whereas blacks and Hispanics were twice as likely.

One of the great advances in medical practice arose from studies on atrial fibrillation in the 1990s.

Low-density lipoprotein (LDL) cholesterol-lowering therapy decreases C-reactive protein (CRP) levels, but the importance of LDL cholesterol-independent effects is uncertain because of the variability in measuring LDL cholesterol and CRP levels in any individual patient. In this study, this variability was reduced by comparing average changes in LDL cholesterol and CRP levels after treatment with lipid-lowering therapy across different studies.