Cardioembolic stroke.

Cardiac sources of emboli account for over one quarter of all ischemic strokes. Strokes due to cardioembolism are in general severe and prone to early and long-term recurrence. Nonvalvular atrial fibrillation remains the most common cause of cardioembolic stroke. Despite the proven efficacy of oral anticoagulation, it is prescribed for less than half of the patients with risk factors for embolism and no contraindications for anticoagulation. The embolic risk of patent foramen ovale is low except when combined with an atrial septal aneurysm. Aortic arch atheroma as an independent risk factor for ischemic stroke is the subject of ongoing debate. As the risk of embolism is heterogeneous for the various potential cardioembolic conditions, accurate definition of stroke mechanism is very important to guide the most effective therapy.

Endovascular repair of abdominal aneurysms: Is this the method of choice?

BACKGROUND: The prevalence of abdominal aneurysms has increased due to the aging population, and endovascular repair has developed into an effective, less invasive treatment. METHODS/RESULTS: Two recent cases at the University of Texas-Houston highlight a variety of clinical considerations that allow informed decision-making regarding optimal treatment of abdominal aneurysms. A thorough discussion of recent data summarizes the current understanding and techniques regarding abdominal aortic aneurysm repair. CONCLUSIONS: Endovascular repair of abdominal aortic aneurysms has emerged as a viable and a safe alternative to surgical repair and may offer important advantages in a majority of patients with this disease.

West Nile virus infection after cardiac transplantation.

West Nile virus is a mosquito-borne RNA Flavivirus infection transmitted to humans and other vertebrates, mainly by the Culex species of mosquito. Since the mid-1990s, the frequency and apparent clinical severity of West Nile virus outbreaks have increased. We report the case of a patient who developed West Nile virus encephalitis shortly after undergoing cardiac transplantation. Clinicians should be aware of the possibility of West Nile virus infection in transplant recipients and in patients receiving blood transfusions.

The use of brachytherapy to treat renal artery in-stent restenosis.

The percutaneous treatment of renal artery stenosis has become the accepted revascularization strategy by most physicians treating this disorder. Unfortunately, as renal artery angioplasty and stent implantation become increasingly prevalent the Achilles heel of angioplasty, in-stent restenosis, also rises. There are currently no data suggestive of the optimal treatment strategy for renal artery in-stent restenosis. However, given the similarities in the pathophysiology between renal artery and coronary artery in-stent restenosis, brachytherapy is considered a reasonable option. This is the strategy that has been suggested and used by a number of operators. This case report describes two examples of renal artery in-stent restenosis treated with angioplasty and brachytherapy.

Electrocardiographic findings in primary systemic amyloidosis and biopsy-proven cardiac involvement.

The electrocardiograms of 127 patients with primary systemic amyloidosis and biopsy-proved cardiac involvement were analyzed. Low voltage (46%) and a pseudoinfarct pattern (47%) were the most common findings. Criteria for left ventricular hypertrophy were present in 16% of patients.

Effect of long-term hormone replacement therapy on coronary endothelial function in postmenopausal women.

OBJECTIVES: To determine the difference in endothelial function between premenopausal and postmenopausal women and to determine whether hormone replacement therapy (HRT) is associated with an improvement in coronary endothelial function. PATIENTS AND METHODS: Women undergoing coronary physiology studies for chest pain at the Mayo Clinic In Rochester, Minn, between December 1992 and April 2002 underwent assessment of coronary endothelium-independent and -dependent function with intracoronary administration of adenosine and acetylcholine, respectively. The coronary diameters, coronary blood flows, and coronary velocity reserves were measured. RESULTS: A total of 270 women (89 premenopausal and 181 postmenopausal) participated in the study. Endothelium-dependent coronary blood flow change (baseline to peak flow) in response to acetylcholine (10(-4), 10(-5), and 10(-4) mol/L) was lower in postmenopausal women compared with premenopausal women (39.7% vs 72.9%, P = .03). There was no significant difference between the postmenopausal women receiving and not receiving HRT with regard to percent change in coronary diameter (-21.8% vs -13.9%, P = .15), percent change in coronary blood flow (37.3% vs 42.7%, P = .74), or coronary velocity reserve (2.7 vs 2.7, P = .82). CONCLUSION: This study shows that the postmenopausal state is associated with a greater abnormality in coronary endothelial function at the level of the microcirculation. Moreover, HRT status was not associated with an improvement in coronary endothelial function in postmenopausal women.

Inflammation and atherosclerosis in acute coronary syndromes.

We review the role of inflammation in coronary artery disease, particularly its conversion from a chronic to an acute illness. An overview is provided of the various biochemical reactions that are grouped under the heading of inflammation and which lead to the development and progression of atherosclerotic vascular disease and its clinical consequences, especially acute coronary syndromes. The potential role of inflammatory markers in identifying patients at risk and for primary and secondary prevention of events is explored. The impact of current pharmacologic therapies on inflammation and possible future medicines are also discussed.

The Accoson Greenlight 300, the first non-automated mercury-free blood pressure measurement device to pass the International Protocol for blood pressure measuring devices in adults.

BACKGROUND: Accurate blood pressure measurement is critical to successful care of the hypertensive patient. The mercury manometer is rapidly being removed from clinical practice due to concerns about environmental contamination. The Accoson Greenlight 300 device is the first non-automated mercury-free device for auscultatory blood pressure measurement to pass the International Protocol for validation of blood pressure measuring devices in adults. METHODS: Fifty-one patients were enrolled to obtain the 33 patients required to fill the three systolic blood pressure (SBP) ranges (low 90-129 mmHg, medium 130-160 mmHg, high 161-180 mmHg) and diastolic blood pressure (DBP) ranges (low 40-79 mmHg, medium 80-100 mmHg, high 101-130 mmHg). Nine sequential blood pressure measurements by two observers with the mercury manometer and the supervisor with the Greenlight 300 were taken. The first two observer blood pressures were used to classify the SBP and DBP range. The readings were then analyzed in two phases to determine whether the device passed the International Protocol. RESULTS: The device passed Phase 1 using 15 subjects. In Phase 2.1 (n=33) for the 99 readings of SBP, 84 of 99 were within 5 mmHg, 95 of 99 were within 10 mmHg, and 98 of 99 were within 15 mmHg. For the 99 readings of DBP, 74 of 99 were within 5 mmHg, 90 of 99 were within 10 mmHg, and 96 of 99 were within 15 mmHg. In Phase 2.2 (n=33) for SBP, 33 of 33 had 2 of 3 SBP within 5 mmHg and none had all three readings >or=5 mmHg. For DBP, 27 of 33 had 2 of 3 of their DBP within 5 mmHg and only three had all three readings > or =5 mmHg. CONCLUSIONS: The Accoson Greenlight 300 is the first electronic non-automated blood pressure measurement device to pass the International Protocol.

Role of incremental doses of intracoronary adenosine for fractional flow reserve assessment.

BACKGROUND: The achievement of maximal vasodilatation of the coronary microvessels is mandatory for the accurate determination of fractional flow reserve (FFR); the optimal dosing to achieve maximal vasodilation is unclear. This study was designed to address the hypothesis that incremental doses of intracoronary adenosine are necessary to ensure complete vasodilatation of the coronary microcirculation and accurate assessment of FFR. We also examined the relationship between FFR and coronary artery disease risk factors. METHODS: A total of 191 patients (215 vessels) with intermediate coronary lesions were examined. FFR was measured during cardiac catheterization with a pressure monitoring wire. Incremental doses of intracoronary adenosine (12-42 microg, left coronary artery; 12-48 microg, right coronary artery) were administered. RESULTS: Diabetes mellitus was present in 23% of patients, hypertension was present in 65% of patients, and prior myocardial infarction had occurred in 25% of patients. The average percent stenosis in vessels was 57% +/- 15%. Vessels were subdivided on the basis of initial FFR (group 1, <0.75; group II, 0.75-0.79; group III, 0.80-0.89; group IV, >or=0.9). Five of the 24 (21%) vessels with an initial FFR in the 0.75 to 0.80 range had a subsequent FFR of <0.75. There was no difference in FFR or doses of adenosine in the patients with coronary artery disease risk factors. The average adenosine dose given at the achievement of minimal FFR was 26 microg in the right coronary artery (RCA) and 34 microg in the left coronary artery (LCA). The average maximum dose of intracoronary adenosine administered was 29 microg for the RCA and 37 microg for the LCA. The maximum dose of adenosine ever required to achieve minimum FFR was 42 microg in both the LCA and RCA. CONCLUSION: This study suggests that a single high dose of 42 microg of intracoronary adenosine for both the RCA and LCA is sufficient to achieve maximum hyperemia and accurate FFR in most patients, independent of risk factors. Alternatively, when a lower initial dose is administered and FFR is in the 0.75 to 0.90 range, incremental doses of adenosine should be administered to ensure maximal hyperemia.

Diagnosis and management of bacterial endocarditis in 2003.

The diagnosis of infective endocarditis has been notoriously difficult. Over the last decade, the modified Duke criteria have assumed an increasingly important role in the early detection of this often occult disease. Echocardiography has assumed increasing importance. Transesophageal echocardiography is recognized as more sensitive and specific than transthoracic echocardiography at detecting vegetations less than 10 mm in diameter. Vegetations greater than 10 mm in diameter are thought to be at increased risk of embolizing. Combined medical and surgical medical management result in the lowest mortality for those patients with hemodynamic compromise.