Multidetector CT coronary angiography: where we are, and where we are going...
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to John R Lesser.
Explore the source record for details and available documents.
INTRODUCTION: Multislice CT coronary angiography (MSCTA) accurately detects stenosis in patients undergoing coronary arteriography, but its accuracy in clinical outpatients is less certain. This study retrospectively analyzed MSCTA performance in a large outpatient cohort and examined 6-month clinical follow-up in those without invasive CA. METHODS: Patients underwent MSCTA for clinical indications including symptoms or noninvasive results being either equivocal or suspected as incorrect by referring clinicians. Standard 16-slice CT scanner techniques were used, and results were analyzed on the basis of both patient and vessel. Patients were treated medically or sent to invasive angiography on the basis of MSCTA results and judgment of referring clinicians. All invasive angiograms were analyzed using quantitative coronary angiography. Six-month clinical follow-up was determined in patients without CA. RESULTS: One thousand fifty-three consecutive patients were referred for MSCTA, resulting in 994 interpretable scans. Mean age was 58+/-13 years, 55% were male, 50% had prior noninvasive testing, and 90% had symptoms. Invasive angiography was performed in 160 patients, with significant stenoses present in 69%. MSCTA demonstrated 87% and 89% accuracy by patient- and vessel-based analysis, respectively, and was most accurate in the left main and right coronary arteries. Only two patients not referred for angiography had significant stenosis in those undergoing 6-month follow-up. CONCLUSIONS: MSCTA accurately detects obstructive coronary stenosis in clinical patients with possible cardiac symptoms, and effectively triages them for invasive angiography. Negative results are highly accurate in ruling out obstructive disease. Six-month prognosis is excellent in patients without significant disease determined by MSCT.
Explore the source record for details and available documents.
BACKGROUND: End stage (ES) is a recognized part of the hypertrophic cardiomyopathy (HCM) disease spectrum. Frequency, clinical profile and course, and treatment strategies in these patients remain incompletely defined. METHODS AND RESULTS: Three HCM cohorts comprised 1259 patients, including 44 (3.5%) characterized as ES with systolic dysfunction (ejection fraction <50% at rest; range 15% to 49%). ES developed at a wide age range (14 to 74 years), with 45% of patients < or = 40 years old. Although 29 patients (66%) died of progressive heart failure, had sudden death events, or underwent heart transplantation, 15 (34%) survived with medical management over 3+/-3 years. Duration from onset of HCM symptoms to ES identification was considerable (14+/-10 years), but ES onset to death/transplantation was brief (2.7+/-2 years). ES occurred with similar frequency in patients with or without prior myectomy (P=0.84). Appropriate defibrillator interventions were 10% per year in patients awaiting donor hearts. Most ES patients (n=23; 52%) showed substantial left ventricular (LV) remodeling with cavity dilatation. Less complete remodeling occurred in 21 patients (48%), including 5 with persistence of a nondilated and markedly hypertrophied LV. Pathology and magnetic resonance imaging showed extensive (transmural) fibrosis in 9 of 11 ES patients. At initial evaluation, patients who developed ES were younger with more severe symptoms, had a larger LV cavity, and more frequently had a family history of ES than other HCM patients. CONCLUSIONS: ES of nonobstructive HCM has an expanded and more diverse clinical expression than previously appreciated, including occurrence in young patients, heterogeneous patterns of remodeling, frequent association with atrial fibrillation, and impaired LV contractility that precedes cavity dilatation, wall thinning, and heart failure symptoms. ES is an unfavorable complication (mortality rate 11% per year) and a sudden death risk factor; it requires vigilance to permit timely recognition and the necessity for defibrillator implantation and heart transplantation.
Left ventricular apical aneurysms, in absence of coronary artery disease, occur in approximately 1% of patients with hypertrophic cardiomyopathy (HC). Identical twins, age 44 years, are presented with HC and identical LV morphology, including apical aneurysms. These cases demonstrate a genetic predisposition to the development of apical aneurysm, as well as overall LV morphology, in patients with HC.
OBJECTIVES: We wished to determine the feasibility and early safety of external beam radiation therapy (EBRT) used following balloon aortic valvuloplasty (BAV) to prevent restenosis. BACKGROUND: BAV for calcific aortic stenosis (AS) has been largely abandoned because of high restenosis rates, i.e., > 80% at 1 year. Radiation therapy is useful in preventing restenosis following vascular interventions and treating other benign noncardiovascular disorders. METHODS: We conducted a 20-patient, pilot study evaluating EBRT to prevent restenosis following BAV in elderly patients with calcific AS. Total doses ranging from 12-18 Gy were delivered in fractions over a 3-5 day post-op period to the aortic valve. Echocardiography was performed pre and 2 days post-op, 1, 6, and 12 months following BAV. RESULTS: One-year follow-up is completed (age 89 +/- 4). There were no complications related to EBRT. Eight patients died prior to 1 year; 5 of 10 (50%) in the low-dose (12 Gy) group and 3 of 10 (30%) in the high-dose (15-18 Gy) group. None of these 8 patients had restenosis, i.e., > 50% loss of the initial AVA gain, and only three deaths were cardiac in origin. One patient underwent aortic valve replacement and none repeated BAV. By 1 year, 3 of the initial 10 (30%) in the low-dose group and 1 of 9 (11%) in the high-dose group demonstrated restenosis (21% overall). CONCLUSIONS: EBRT following BAV in elderly patients with AS is feasible, free of early complications, and holds promise in reducing the 1 year restenosis rate in a dose-dependent fashion.
BACKGROUND: A clinical entity characterized by acute but rapidly reversible left ventricular (LV) systolic dysfunction and triggered by psychological stress is emerging, with reports largely confined to Japan. METHODS AND RESULTS: Over a 32-month period, 22 consecutive patients with this novel cardiomyopathy were prospectively identified within a community-based practice in the Minneapolis-St. Paul, Minn, area. All patients were women aged 32 to 89 years old (mean 65+/-13 years); 21 (96%) were > or =50 years of age. The syndrome is characterized by (1) acute substernal chest pain with ST-segment elevation and/or T-wave inversion; (2) absence of significant coronary arterial narrowing by angiography; (3) systolic dysfunction (ejection fraction 29+/-9%), with abnormal wall motion of the mid and distal LV, ie, "apical ballooning"; and (4) profound psychological stress (eg, death of relatives, domestic abuse, arguments, catastrophic medical diagnoses, devastating financial or gambling losses) immediately preceding and triggering the cardiac events. A significant proportion of patients (37%) had hemodynamic compromise and required vasopressor agents and intra-aortic balloon counterpulsation. Each patient survived with normalized ejection fraction (63+/-6%; P<0.001) and rapid restoration to previous functional cardiovascular status within 6+/-3 days. In 95%, MRI identified diffusely distributed segmental wall-motion abnormalities that encompassed LV myocardium in multiple coronary arterial vascular territories. CONCLUSIONS: A reversible cardiomyopathy triggered by psychologically stressful events occurs in older women and may mimic evolving acute myocardial infarction or coronary syndrome. This condition is characterized by a distinctive form of systolic dysfunction that predominantly affects the distal LV chamber and a favorable outcome with appropriate medical therapy.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
PURPOSE: To compare the accuracy of multisection true fast imaging with steady-state precession (FISP) with gadolinium-enhanced magnetic resonance (MR) angiography for the detection of coronary artery bypass graft patency. MATERIALS AND METHODS: Twenty-five patients with coronary artery bypass grafts who had recently undergone conventional coronary angiography underwent MR angiography with a 1.5-T system. True FISP angiographic images were acquired in transverse and coronal planes. Coronal cardiac-gated MR angiography was performed with 0.2 mL per kilogram of body weight of gadopentetate dimeglumine injected at a rate of 2 mL/sec. With conventional angiography as the reference standard, the sensitivity, specificity, and accuracy of each technique for the detection of graft patency were determined. Image quality and duration of analysis were determined by two experienced radiologists. RESULTS: In 25 patients, 46 of 56 venous grafts were patent and 22 of 23 arterial grafts were patent. In all grafts at true FISP angiography, sensitivity for patency was 84% (57 of 68 grafts), specificity was 45% (five of 11 grafts), and accuracy was 78% (62 of 79 grafts). At MR angiography, sensitivity was 85% (58 of 68 grafts), specificity was 73% (eight of 11 grafts), and accuracy was 84% (66 of 79 grafts) (difference not significant). Image quality scores were similar with both techniques, but duration of analysis was significantly longer with MR angiography than with true FISP angiography (29 minutes 24 seconds vs 14 minutes 6 seconds, P <.001). CONCLUSION: Accuracy for detection of coronary artery bypass graft patency was similar with gadolinium-enhanced MR angiography and true FISP angiography, with a trend toward more false-positive findings for occlusion and reduced visualization of arterial grafts with true FISP angiography.
BACKGROUND: The influence of left ventricular outflow tract obstruction on the clinical outcome of hypertrophic cardiomyopathy remains unresolved. METHODS: We assessed the effect of outflow tract obstruction on morbidity and mortality in a large cohort of patients with hypertrophic cardiomyopathy who were followed for a mean (+/-SD) of 6.3+/-6.2 years. RESULTS: Of the 1101 consecutive patients, 273 (25 percent) had obstruction of left ventricular outflow under basal (resting) conditions with a peak instantaneous gradient of at least 30 mm Hg. A total of 127 patients (12 percent) died of hypertrophic cardiomyopathy, and 216 surviving patients (20 percent) had severe, disabling symptoms of progressive heart failure (New York Heart Association [NYHA] functional class III or IV). The overall probability of death related to hypertrophic cardiomyopathy was significantly greater among patients with outflow tract obstruction than among those without obstruction (relative risk, 2.0; P=0.001). The risk of progression to NYHA class III or IV or death specifically from heart failure or stroke was also greater among patients with obstruction (relative risk, 4.4; P<0.001), particularly among patients 40 years of age or older (P<0.001). Age-adjusted multivariate analysis confirmed that outflow tract obstruction was independently associated with an increased risk of both death related to hypertrophic cardiomyopathy (relative risk, 1.6; P=0.02) and progression to NYHA class III or IV or death from heart failure or stroke (relative risk, 2.7; P<0.001). The likelihood of severe symptoms and death related to outflow tract obstruction did not increase as the gradient increased above the threshold of 30 mm Hg. CONCLUSIONS: In patients with hypertrophic cardiomyopathy, left ventricular outflow tract obstruction at rest is a strong, independent predictor of progression to severe symptoms of heart failure and of death.
The concept of the vulnerable patient has arrived. Enhanced diagnostic methods will eventually permit accurately finding and treating these patients and their disease. Clinical Cardiologists now recognize that coronary atherosclerosis is two pathophysiologically distinct syndromes: stable and unstable. Stable coronary syndromes result from fixed, severe stenoses limiting blood flow and causing secondary myocardial ischemia. The unstable acute coronary syndromes are frequently catastrophic and are pathophysiologically distinct. They result from different cell subsets causing vascular inflammatory syndromes rather than gradual lumen constriction by plaque. Though pathophysiologically distinct, they may show common pathophysiology when a ruptured plaque heals and progressively becomes a critical stenosis. For the present hs-CRP measurement is the strongest correlative factor for future clinical events due to arterial inflammation: myocardial infarction, unstable angina, stroke, and peripheral vascular disease in both diseased and apparently healthy, asymptomatic patients. The CRP plasma level also is the best risk assessment in patients with either stable or unstable angina, long term after myocardial infarction, and in patients undergoing revascularization therapies. One study showed the only independent cardiovascular risk indicators using multivariate, age adjusted and traditional risk analysis were CRP and Total/HDL cholesterol ratio. If CRP, IL-6, and ICAM-1 levels are added to lipid levels, risk assessment can be improved over lipids alone. The prevalence of high-risk subjects in the general population is low, amplifying diagnostic problems for vulnerable plaque. Since no test yet has high sensitivity or specificity, diagnostic errors are high, with many false positives and negatives. Sensitivity or specificity must be increased by developing a risk marker panel, or by simultaneously finding other markers that themselves are highly sensitive and specific for vulnerable plaque.