Non-Q Wave Myocardial Infarction

Non-Q wave myocardial infarction is a distinct and changing clinical entity characterized by lower initial mortality and a higher rate of reinfarction compared to Q wave infarction. Clinical and pathologic data suggest that the syndrome results from transient or incomplete coronary occlusion resulting in an infarct which is smaller than when Q waves are present. High-risk patients can be identified during hospitalization, allowing for aggressive therapy aimed at revascularization. Relatively few clinical trials have examined initial therapy or secondary prevention in this group of patients. These studies are reviewed and management guidelines suggested

Left ventricular shape is the primary determinant of functional mitral regurgitation in heart failure

AbstractObjectives. The aim of this study was to examine the temporal association between the onset of functional mitral regurgitation and the development of changes in left ventricular shape, chamber enlargement, mitral anulus dilation and regional wall motion abnormalities during the course of evolving heart failure.Background. Despite extensive characterization, the exact etiology of functional mitral regurgitation in patients with chronic heart failure remains unknown.Methods. Heart failure was produced in seven dogs by multiple sequential intracoronary microembolizations. Serial changes in left ventricular chamber volume and shape were evaluated from ventriculograms. Changes in mitral anulus diameter and ventricular regional wall motion abnormalities were evaluated echocardiographically. The presence and severity of mitral regurgitation were determined with Doppler color flow mapping. Measurements were obtained at baseline and then biweekly until mitral regurgitation was first observed.Results. No dag had mitral regurgitation at baseline but all developed mild to moderate regurgitation 12 ± 1 weeks after the first embolization. The onset of mitral regurgitation was not associated with an increase in left ventricular end-diastolic volume relative to baseline (58 ± 3 vs. 62 ± 3 ml), mitral anulus diameter (2.4 ± O.1 vs. 2.4 ± 0.1 cm) or wall motion abnormalities of left ventricular wall segments overlying the papillary muscles. In contrast, the onset of mitral regurgitation was accompanied by significant changes in global left ventricular shape evidenced by increased end-systolic chamber sphericity index (0.22 ± 0.02 vs. 0.30 ± 0.01) (p < 0.01) and decreased end-systolic major axis/ minor axis ratio (1.71 ± 0.05 vs. 1.43 ± 0.04) (p < 0.001).Conclusions. These data indicate that transformation of left ventricular shape (increased chamber sphericity) is the most likely substrate for the development of functional mitral regurgitation

Porcine Bioprosthetic Aortic Valve Endocarditis with Ring Abscess and Aortic Stenosis

Porcine bioprosthetic valve endocarditis is an infrequent but serious complication of valve replacement surgery. Ring (or annular) abscess is a frequent finding in mechanical valve endocarditis. In contrast, porcine valve endocarditis most often involves the cusps, and annular infection is uncommon. Porcine valvular dysfunction secondary to endocarditis usually takes the form of incompetence, whereas stenosis is less frequent. We report a case of a 76-year-old female who developed endocarditis wilh Staphylococcus epidermidis nine months after placement of a Carpenter-Edwards porcine aortic valve. Her initial presentation included complete heart block and moderate aortic stenosis. Transesophageal echocardiography aided the diagnosis by demonstrating large vegetations, while transthoracic echocardiography showed only slight thickening of the valve leaflets. At operation, there was a circumferential abscess around the sewing ring causing valve dehiscence and virtual discontinuity of the aorta from the left ventricle. Valve degeneration and organisms within the cusps were observed on microscopy. This case illustrates two infrequent complications of porcine aortic valve endocarditis, namely massive annular abscess with invasion of the conducting system and aortic stenosis. It also demonstrates the utility and limitations of transesophageal echocardiography in the diagnosis of this disorder

Practical Value of Echo Doppler Evaluation of Aortic and Mitral Stenosis: A Comparative Study with Cardiac Catheterization

This retrospective analysis compares data derived by echocardiography and cardiac catheterization in the evaluation of aortic and mitral valve stenosis. Sixty-seven patients, aged 69 ± 12 years, underwent 76 catheterization procedures. In all studies the Doppler recording was technically adequate. In 64 studies of patients with aortic stenosis, correlation was good between the gradient obtained at catheterization (peak 51 ± 28 mm Hg, mean 48 ± 24 mm Hg) and the Doppler gradient (peak 73 ± 29 mm Hg, mean 41 ±17 mm Hg) (R = 0.78 peak, 0.77 mean). In 15 studies the aortic valve area, 0.8 ± 0.2 cm2, calculated by the simplified continuity equation, correlated well with the catheterization valve area, 0.7 + 0.3 cm2, calculated by the Gorlin equation (R = 0.80). In 14 studies in mitral stenosis patients, the mean gradient at catheterization was 11 ±5 mmHg compared to the Doppler gradient of 8 ±4 mmHg (R = 0.58). The mitral valve area was 1.1 ± 0.3 cm2 by the Gorlin equation and 1.2 ± 0.3 cm2 by echo Doppler, using pressure half-time. When cardiac rhythm, the presence and severity of regurgitation, and the cardiac index were analyzed, none was shown to have demonstrable influence cm the accuracy of the Doppler study. Doppler echocardiography can be used reliably to assess valvular stenosis in a clinical, noninvasive laboratory where routine tests are performed and interpreted by more than one individual

Relationship Between Carotid Disease on Ultrasound and Coronary Disease on CT Angiography

ObjectivesThe purpose of this study was to assess the relationship between carotid artery disease by ultrasound and coronary artery disease by coronary computed tomography angiography (CTA) and to identify carotid ultrasound parameters predictive of coronary artery disease.BackgroundCarotid ultrasound and CTA are noninvasive modalities used to image atherosclerosis. Studies examining the relationship between the 2 tests, however, are lacking.MethodsWe performed carotid ultrasound on predominantly nondiabetic subjects referred for CTA. Carotid intima media thickness (IMT) and plaque were assessed and compared with coronary artery calcification and the number of coronary arteries with any evidence of atherosclerosis on CTA.ResultsA total of 150 subjects underwent both CTA and carotid ultrasound on the same day. Carotid plaque was present in 71.3% (n = 107), whereas the presence of at least 1 coronary artery with disease on CTA was present in 57.1% (n = 84). Carotid plaque was present in 47.6% (30 of 63) of subjects with a calcium score of 0 and 88.5% (77 of 87) of subjects with a calcium score >0 (p = 0.0001). Similarly carotid plaque was present in 52.4% (33 of 63) of subjects with no CTA evidence of atherosclerosis versus 85.7% (72 of 84) of subjects with any CTA evidence of atherosclerosis (p < 0.0001). Carotid plaque, IMT ≥1.5 mm, or averaged mean IMT >0.75 mm were associated with a calcium score >0 (odds ratio: 5.4, p < 0.0001, 2.7, p < 0.001; 2.9, p = 0.011, respectively) and disease in at least 1 vessel on CTA (odds ratio: 2.8, p = 0.03, 2.19, p = 0.073; 2.22, p = 0.058, respectively) independent of age and sex.ConclusionsCarotid plaque and increased carotid IMT are associated with the presence and severity of coronary calcification and disease on CTA in ambulatory subjects

Association of Operator and Hospital Experience With Procedural Success Rates and Outcomes in Patients Undergoing Percutaneous Coronary Interventions for Chronic Total Occlusions: Insights From the Blue Cross Blue Shield of Michigan Cardiovascular Consortium

BACKGROUND: An inverse relationship has been described between procedural success and outcomes of all major cardiovascular procedures. However, this relationship has not been studied for percutaneous coronary intervention (PCI) of chronic total occlusion (CTO). METHODS: We analyzed the data on patients enrolled in Blue Cross Blue Shield of Michigan Cardiovascular Consortium registry in Michigan (January 1, 2010 to March 31, 2018) to evaluate the association of operator and hospital experience with procedural success and outcomes of patients undergoing CTO-PCI. CTO-PCI was defined as intervention of a 100% occluded coronary artery presumed to be ≥3 months old. RESULTS: Among 210 172 patients enrolled in the registry, 7389 (3.5%) CTO-PCIs were attempted with a success rate of 53%. CTO-PCI success increased with operator experience (45% and 65% in the lowest and highest experience tertiles) and was the highest for highly experienced operators at higher experience centers and the lowest for inexperienced operators at low experience hospitals. Multivariable logistic regression models (with spline transformed prior operator and institutional experience) demonstrated a positive relationship between prior operator and site experience and procedural success rates (likelihood ratio test=141.12, df=15, P\u3c0.001) but no relationship between operator and site experience and major adverse cardiac event (likelihood ratio test=19.12, df=15, P=0.208). CONCLUSIONS: Operator and hospital CTO-PCI experiences were directly related to procedural success but were not related to major adverse cardiac event among patients undergoing CTO-PCIs. Inexperienced operators at high experience centers had significantly higher success but not major adverse cardiac event rates compared with inexperienced operators at low experience centers. These data suggested that CTO-PCI safety and success could potentially be improved by selective referral of these procedures to experienced operators working at highly experienced centers

Design and recruitment in the United States of a multicenter quantitative angiographic trial of pravastatin to limit atherosclerosis in the coronary arteries (PLAC I)

The present study was designed to test the effect of pravastatin, a new, 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, on the progression of coronary artery disease in patients with moderate hypercholesterolemia. Angiographic entry criteria included the presence of &gt;=1 stenosis &gt;=50% in a major epicardial coronary artery, and certification of film quality through the core angiography laboratory. Patients qualified for randomization if after diet stabilization their low density lipoprotein cholesterol concentrations were &gt;=130 and &lt; 190 mg/dl, and triglycerides were &lt;= 350 mg/dl. Pravastatin (40 mg) or placebo is administered once daily at bedtime. Arteriography will be repeated at the end of 3 years of treatment. The primary end point of the study is the change in absolute mean coronary artery diameter. During a 30-month recruitment period, 44,145 patients were screened, and 408 were randomized. The most frequent reason for excluding patients during the screening and dietary lead-in periods was a low serum cholesterol level. A large proportion of patients with documented coronary artery disease have cholesterol concentrations that are considered to be normal or only modestly increased. Adherence to strict standards of quality control for digital analysis of angiograms ensures that baseline angiograms can be interpreted at the end of 3-year follow-up.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/30692/1/0000337.pd

Efficacy and safety of pravastatin in the long-term treatment of elderly patients with hypercholesterolemia

Elevated cholesterol levels are a major risk factor for coronary heart disease, which remains a significant problem in patients beyond age 65 years. Because drug therapy for the control of hypercholesterolemia in elderly patients is frequently considered to be indicated, we investigated the efficacy and safety of pravastatin in the treatment of elderly subjects with primary hypercholesterolemia. In this 96-week, multicenter, double-blind, placebo-controlled study, 142 subjects (95 women, 47 men) 64 to 90 years of age with elevated cholesterol levels despite dietary intervention were randomized to receive pravastatin 20 mg at bedtime or matching placebo (2:1). Dosage could be doubled after 8 weeks, a bile acid-binding resin could be added after 16 weeks, and nicotinic acid or probucol could be added after 32 weeks, as needed, to adequately lower the low-density lipoprotein cholesterol (LDL-C) levels. Significant reductions in the levels of LDL-C (-30.9%), total cholesterol (Total-C; -21.9%), and triglycerides (TG; -16.7%) and significant increases in the levels of high-density lipoprotein cholesterol (HDL-C; 11.3%) were noted in the group receiving pravastatin treatment at 16 weeks (P In this study, pravastatin was well tolerated and effective in lowering LDL-C, Total-C, and TG and in raising HDL-C during long-term treatment of elderly patients with primary hypercholesterolemia.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/31935/1/0000888.pd