Predictive value of reactive hyperemia for cardiovascular events in patients with peripheral arterial disease undergoing vascular surgery.

OBJECTIVE: Reactive hyperemia is the compensatory increase in blood flow that occurs after a period of tissue ischemia, and this response is blunted in patients with cardiovascular risk factors. The predictive value of reactive hyperemia for cardiovascular events in patients with atherosclerosis and the relative importance of reactive hyperemia compared with other measures of vascular function have not been previously studied. METHODS AND RESULTS: We prospectively measured reactive hyperemia and brachial artery flow-mediated dilation by ultrasound in 267 patients with peripheral arterial disease referred for vascular surgery (age 66+/-11 years, 26% female). Median follow-up was 309 days (range 1 to 730 days). Fifty patients (19%) had an event, including cardiac death (15), myocardial infarction (18), unstable angina (8), congestive heart failure (6), and nonhemorrhagic stroke (3). Patients with an event were older and had lower hyperemic flow velocity (75+/-39 versus 95+/-50 cm/s, P=0.009). Patients with an event also had lower flow-mediated dilation (4.5+/-3.0 versus 6.9+/-4.6%, P<0.001), and when these 2 measures of vascular function were included in the same Cox proportional hazards model, lower hyperemic flow (OR 2.7, 95% CI 1.2 to 5.9, P=0.018) and lower flow-mediated dilation (OR 4.2, 95% CI: 1.8 to 9.8, P=0.001) both predicted cardiovascular events while adjusting for other risk factors. CONCLUSIONS: Thus, lower reactive hyperemia is associated with increased cardiovascular risk in patients with peripheral arterial disease. Furthermore, flow-mediated dilation and reactive hyperemia incrementally relate to cardiovascular risk, although impaired flow-mediated dilation was the stronger predictor in this population. These findings further support the clinical relevance of vascular function measured in the microvasculature and conduit arteries in the upper extremity.

Giant cell arteritis: diagnosis, management, and cardiovascular implications.

Giant cell arteritis is a relatively common form of systemic vasculitis, best known for its predisposition to affect the extracranial branches of the carotid artery and associated potential for visual loss. Additional vascular manifestations include stroke, aortic aneurysm or dissection, and even aortic rupture. Cardiac manifestations include coronary artery disease, aortic valve insufficiency, or left ventricular dysfunction, which may occur independently from the valvular disease or hypertension. Physicians need to be vigilant for this disorder, particularly because the tragic end-organ outcomes such as visual loss can be effectively prevented with early use of corticosteroids. We review the pathophysiology and clinical manifestations of giant cell arteritis and present a rationale for diagnosis and therapy for this disease.

Anomalous left main coronary artery from the main pulmonary artery in an elderly patient.

Anomalous origin of the left main coronary from the pulmonary trunk in an elderly patient is extremely rare. We report a 73-year-old woman who presented with new onset of angina and atrial fibrillation. Evaluation revealed anomalous origin of the left main coronary artery from the main pulmonary artery and tight proximal left anterior descending coronary artery stenosis. The patient underwent primary closure of the anomalous left main coronary artery orifice within the pulmonary artery, aorta-to-left anterior descending coronary artery saphenous vein bypass grafting and Maze procedure. Six months postoperatively the patient was asymptomatic and a Thallium stress test was negative for ischemia.