Thomas Knickelbine

The value of dobutamine stress echocardiography for the detection of coronary artery disease in women.

To determine whether there were any gender-based differences in the detection of coronary artery disease by dobutamine stress echocardiography, we examined 288 patients (187 men and 101 women) who underwent coronary angiography within 8 weeks of dobutamine stress testing. Abnormal test results were indicated by let ventricular wall motion abnormalities at rest, which did not improve or worsen, or inducible wall motion abnormalities in two or more segments with dobutamine. Overall, dobutamine stress echocardiography showed a high sensitivity, specificity, and accuracy in both men and women: 85%, 96%, and 88% anx 90%, 79%, and 86%, respectively. The sensitivity in detecting significant coronary artery disease in our population was not influenced by gender. However, the sensitivity of the test was influenced by the extent and location of coronary disease and the pattern of left ventricular, hypertrophy. The sensitivity was 80% in patients with single-vessel disease, whereas the sensitivity was 91% in patients with multivessel disease. In addition, patients with single-vessel disease had lower sensitivity when the abnormality was located in the left circumflex coronary artery territory (59% versus 86% in the left anterior descending and right coronary territories). Our data indicated that there is no gender-based difference in the sensitivity and specificity of dobutamine stress echocardiography in detecting coronary artery disease and that the limitations of the test should be attributed to the extent and location of coronary disease.

Clinical utility of coronary CT angiography: coronary stenosis detection and prognosis in ambulatory patients.

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 signficant 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.

Prevalence of the American Heart Association's "ideal cardiovascular health" metrics in a rural, cross-sectional, community-based study: the Heart of New Ulm Project.

Background The American Heart Association (AHA) recently created the construct of “ideal cardiovascular health” based on 7 cardiovascular health metrics to measure progress toward their 2020 Impact Goal. The present study applied this construct to assess the baseline cardiovascular health of a rural population targeted with a community‐based cardiovascular disease prevention program. Methods and Results The sample consists of 4754 New Ulm, Minn, adult residents who participated in either the 2009 or 2011 community heart health screenings offered by the Hearts Beat Back: The Heart of New Ulm (HONU) Project (mean age 52.1 years, 58.3% women). Data collected at the screenings were analyzed to replicate the AHAs ideal cardiovascular health measure and the 7 metrics that comprise the construct. Screening participants met, on average (±SD), 3.4 (±1.4) ideal cardiovascular health metrics. Only 1.0% of participants met the AHAs definition of ideal health in all metrics and 7.1% met ≤1 ideal health metric. Higher proportions of women met the ideal category in all metrics except physical activity. Women over the age of 60 were less likely to meet the ideal category for cholesterol and hypertension than were men in the same age range. Conclusion Prevalence of ideal cardiovascular health is extremely low in this rural population. To make progress toward the 2020 Impact Goal, targeted community‐based interventions must be implemented based on the most prevalent cardiovascular risk factors.

Radiation following percutaneous balloon aortic valvuloplasty to prevent restenosis (RADAR pilot trial)

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.

Identification of unexpected nonatherosclerotic cardiovascular disease with coronary CT angiography.

OBJECTIVES The aim of this study was to assess, in a general cardiology cohort screened for obstructive coronary artery disease (CAD), the effectiveness and frequency with which multidetector computed tomography (MDCT) angiography unexpectedly imaged and identified other nonatherosclerotic cardiovascular diseases. BACKGROUND MDCT angiography is a novel imaging strategy employed primarily to diagnose CAD that, in the course of these studies, can also potentially identify other important but previously unrecognized cardiovascular abnormalities. METHODS Consecutive 64-slice MDCT angiography studies were obtained in 4,543 patients with suspected atherosclerotic CAD at the Minneapolis Heart Institute, over a 29-month period (2005 to 2007). RESULTS Nonatherosclerotic-related cardiovascular abnormalities judged to be of potential clinical relevance were identified in 201 patients (4.4%). In 50 of these patients (1.1% of 4,543) the abnormality was previously unrecognized despite other imaging studies performed in 40%. Most common among the 50 patients were: congenital coronary artery anomalies (38%; largely right coronary artery from the left aortic sinus); ascending aortic aneurysms > or = 45 mm (22%); hypertrophic cardiomyopathy with apical left ventricular (LV) wall thickening (14%); valvular heart diseases (8%), congenital heart diseases, including ventricular septal defect (6%); pulmonary embolus (6%); as well as LV noncompaction, left atrial myxoma, and LV apical aneurysm (2% each). As a consequence of MDCT angiography findings, new management strategies were instituted in 15 of 50 patients (30%), including surgical correction of coronary artery anomalies of wrong sinus origin, ascending aneurysm graft repair, thrombolytic therapy for pulmonary embolism, and myxoma resection. CONCLUSIONS Approximately 1% of patients undergoing MDCT angiography for suspicion of CAD proved to have otherwise unsuspected, but clinically relevant, cardiovascular abnormalities unrelated to coronary atherosclerosis. Almost one-third of these patients had cardiovascular diseases with major clinical implications for subsequent therapy. These findings underscore the value of MDCT angiography and the importance of careful assessment of scans for the recognition of a variety of cardiovascular abnormalities.

Multidetector CT coronary angiography for patient triage to invasive coronary angiography: Performance and cost in ambulatory patients with equivocal or suspected inaccurate noninvasive stress tests†

Background: Multidetector‐CT angiography (MDCTA) differs from noninvasive stress tests by directly imaging coronary anatomy. The utility of MDCTA for invasive triage is undefined however. We evaluated MDCTA triage to invasive coronary angiography in outpatients with indeterminate or suspected inaccurate stress tests, and estimated cost savings by MDCTA in this role. Methods: Consecutive MDCTA patients were retrospectively compared with noninvasive stress tests if performed within 6 months of MDCTA. Twelve‐month clinical follow up was obtained for patients not undergoing invasive angiography, and cost using MDCTA for triage to invasive coronary angiography was calculated. Results: MDCTA was performed in 385 patients who had noninvasive stress testing. Stress tests include included treadmill (n = 37), stress echo (n = 178), and nuclear perfusion imaging (n = 170). Invasive angiography was performed in 57 (14.8%). MDCTA compared to CA showed positive and negative predictive values of 94%/100% respectively for lesions found by invasive QCA. Stress testing compared to MDCTA showed positive/negative predictive values of 100%/67% for treadmill exercise, 60%/54% for stress echo, and 59%/55% of nuclear perfusion examinations respectively. One year clinical follow up in 314 patients showed no coronary events in 98% (309) of patients. Triage to invasive angiography by MDCTA showed a 4‐fold cost reduction. Conclusions: MDCTA shows excellent performance as a triage for invasive angiography in patients with stress tests that are equivocal or thought inaccurate. A negative CTA confers good 12‐month prognosis. Substantial cost savings may accrue using MDCTA in this triage role.

Effect of PCSK9 inhibitors on clinical outcomes in patients with hypercholesterolemia: A meta-analysis of 35 randomized controlled trials

Background We sought to examine the efficacy and safety of 2 PCSK9 (proprotein convertase subtilisin/kexin type 9) inhibitors: alirocumab and evolocumab. Methods and Results We performed a systematic review and meta‐analysis of randomized controlled trials comparing treatment with and without PCSK9 inhibitors; 35 randomized controlled trials comprising 45 539 patients (mean follow‐up: 85.5 weeks) were included. Mean age was 61.0±2.8 years, and mean baseline low‐density lipoprotein cholesterol was 106±22 mg/dL. Compared with no PCSK9 inhibitor therapy, treatment with a PCSK9 inhibitor was associated with a lower rate of myocardial infarction (2.3% versus 3.6%; odds ratio [OR]: 0.72 [95% confidence interval (CI), 0.64–0.81]; P<0.001), stroke (1.0% versus 1.4%; OR: 0.80 [95% CI, 0.67–0.96]; P=0.02), and coronary revascularization (4.2% versus 5.8%; OR: 0.78 [95% CI, 0.71–0.86]; P<0.001). Overall, no significant change was observed in all‐cause mortality (OR: 0.71 [95% CI, 0.47–1.09]; P=0.12) or cardiovascular mortality (OR: 1.01 [95% CI, 0.85–1.19]; P=0.95). A significant association was observed between higher baseline low‐density lipoprotein cholesterol and benefit in all‐cause mortality (P=0.038). No significant change was observed in neurocognitive adverse events (OR: 1.12 [95% CI, 0.88–1.42]; P=0.37), myalgia (OR: 0.95 [95% CI, 0.75–1.20]; P=0.65), new onset or worsening of preexisting diabetes mellitus (OR: 1.05 [95% CI, 0.95–1.17]; P=0.32), and increase in levels of creatine kinase (OR: 0.84 [95% CI, 0.70–1.01]; P=0.06) or alanine or aspartate aminotransferase (OR: 0.96 [95% CI, 0.82–1.12]; P=0.61). Conclusions Treatment with a PCSK9 inhibitor is well tolerated and improves cardiovascular outcomes. Although no overall benefit was noted in all‐cause or cardiovascular mortality, such benefit may be achievable in patients with higher baseline low‐density lipoprotein cholesterol.

Transseptal technique of percutaneous PFO closure results in persistent interatrial shunting

Our goal was to review the effectiveness of the transseptal and tunnel techniques of patent foramen ovale (PFO) closure. Percutaneous PFO closure is an increasingly common treatment for prevention of paradoxical embolism and is typically performed by passing the device through the defect tunnel itself. The transseptal technique, in which the septum primum is punctured to create a hole through which the device is passed, has been proposed for patients with long‐tunnel PFO. From May 2001 to December 2003, 120 patients underwent PFO closure at our institution and were included in this analysis. Defect closure was assessed by transesophageal echocardiography (TEE) with bubble study. Clinical follow‐up data were obtained by clinic visits or standardized telephone interviews. Device closure was successfully completed in all patients, with 12 (10%) undergoing transseptal closure and 108 (90%) undergoing tunnel closure. Immediately following the procedure, complete closure occurred in 6 of 12 (50%) of the transseptal group and 88 of 108 (81.5%) of the tunnel group (P = 0.0120). Of the 89 patients (74.2%) who returned for 6‐month TEE, complete closure was demonstrated in 4 out of 10 (40%) of the transseptal group and 58 out of 79 (73.4%) of the tunnel group (P = 0.0303). There have been four transient ischemic attacks during a mean follow‐up of 11 months. The transseptal technique of PFO closure results in a higher proportion of patients with persistent interatrial shunting when compared with the tunnel technique. Whether this is due to a difference in technique, device, or patient anatomy is unclear.

Underuse of cardiovascular preventive pharmacotherapy in patients presenting with ST-elevation myocardial infarction

BACKGROUND Multiple medications have proven efficacy for the primary prevention of coronary heart disease (CHD), but the appropriate patient population remains controversial. Even in the presence of multiple cardiovascular risk factors, many patients are not considered high risk and are not offered preventive medications despite proven efficacy. METHODS We analyzed a prospective cohort of 1,710 consecutive ST-elevation myocardial infarction (STEMI) patients treated in a regional STEMI system from May 2007 to July 2010 and enrolled in a comprehensive database that includes preadmission medications. RESULTS Of the 1,707 patients analyzed, 1,180 (69.1%) did not have known CHD before their event; and 482 (41.7%) of those patients had premature events (men <55 years old, women <65 years old). In patients without known CHD, cardiovascular risk factors were abundant (52.1% had hypertension, 43.6% had dyslipidemia, 41.4% had a family history of CHD, 58.5% were current or former smokers, and 14.9% were diabetic). Despite the high prevalence of risk factors, only 24.1% were on aspirin, 16.1% were on a statin, and only 7.8% were taking an aspirin and statin. Use of preventive medications was even less common in patients with premature events, including aspirin (15.2% vs 30.2%, P value < .001), statins (11.1% vs 19.5%, P value < .001), and the combination (5.6% vs 9.4%, P value < .001). CONCLUSIONS Approximately 70% of a contemporary STEMI population did not have known CHD before their event, and >40% of those events would be considered premature. Despite the significant burden of cardiovascular risk factors, use of preventive therapy was alarmingly low in patients presenting with STEMI.

Comparison of Diagnostic Quality of Motion Picture Experts Group-2 Digital Video with Super VHS Videotape for Echocardiographic Imaging

BACKGROUND Motion Picture Experts Group-2 (MPEG2) is a broadcast industry standard that allows high-level compression of echocardiographic data. Validation of MPEG2 digital images compared with super VHS videotape has not been previously reported. METHODS Simultaneous super VHS videotape and MPEG2 digital images were acquired. In all, 4 experienced echocardiographers completed detailed reporting forms evaluating chamber size, ventricular function, regional wall-motion abnormalities, and measures of valvular regurgitation and stenosis in a blinded fashion. Comparisons between the 2 interpretations were then performed and intraobserver concordance was calculated for the various categories. RESULTS A total of 80 paired comparisons were made. The overall concordance rate was 93.6% with most of the discrepancies being minor (4.1%). Concordance was 92.4% for left ventricle, 93.2% for right ventricle, 95.2% for regional wall-motion abnormalities, and 97.8% for valve stenosis. The mean grade of valvular regurgitation was similar for the 2 techniques. CONCLUSIONS MPEG2 digital imaging offers excellent concordance compared with super VHS videotape.