Cardiorespiratory Fitness and Coronary Artery Calcification in a Primary Prevention Population.

Objective: To elucidate whether cardiorespiratory fitness (CRF) is protective or contributory to coronary artery disease plaque burden.

Patients And Methods: Study participants were working middle-aged men from the Mayo Clinic Executive Health Program who underwent coronary artery calcium (CAC) assessment and exercise treadmill testing for risk stratification. Data from January 1, 1995, through December 31, 2008, were considered.

Coronary microcirculation changes in non-ischemic dilated cardiomyopathy identified by novel perfusion CT.

Intramyocardial microvessels demonstrate functional changes in cardiomyopathies. However, clinical computed tomography (CT) does not have adequate spatial resolution to assess the microvessels. Our hypothesis is that these functional changes manifest as altered heterogeneity of the spatial distribution of arteriolar perfusion territories.

Diagnostic capability of comprehensive handheld vs transthoracic echocardiography.

Objective: To assess the diagnostic capability of handheld echocardiography (HHE) compared with transthoracic echocardiography (TTE) performed and evaluated by experienced sonographers and expert echocardiographers.

Patients And Methods: We conducted a prospective study of adult outpatients undergoing comprehensive TTE between July 9, 2012, and April 3, 2013. Experienced sonographers performed a detailed, standardized examination using a handheld ultrasound device that included 2-dimensional and color Doppler images from standard imaging windows.

Weight change after a one-time preventive cardiology clinic visit.

Aim: The effect of a one-time visit to a cardiovascular health clinic (CVHC) on weight change remains unknown. Our study examined the effects of such a visit for subjects undergoing medical and preventive evaluations.

Methods: The study screened 836 subjects with a baseline BMI>25 kg/m2 and a follow-up weight at least 6 months from the initial visit.

Early changes in myocardial microcirculation in asymptomatic hypercholesterolemic subjects: as detected by perfusion CT.

Intramyocardial microvessels show functional changes in early stages of atherosclerosis prior to epicardial coronary artery stenosis. However, clinical CT does not have adequate spatial resolution to resolve the microvessels. To clinically detect changes in the function of the intramyocardial microcirculation, the spatial heterogeneity of the distribution of myocardial perfusion (F) and intramyocardial microcirculatory blood volume (Bv) was determined by perfusion CT.

Self-rated stress is noncontributory to coronary artery disease in higher socioeconomic strata.

Stress and its attendant psychosocial and lifestyle variables have been associated with coronary artery disease (CAD), yet the contribution of socioeconomic status (SES) has not been addressed. The aim of this study is to determine if stress assessment is associated with CAD independent of SES, and is incremental to the Framingham Score. The study group consisted of 325 executive patients undergoing comprehensive health assessment.

Outcomes in patients with chest pain evaluated in a chest pain unit: the chest pain evaluation in the emergency room study cohort.

Background: Limited data exist on the long-term outcomes of patients who undergo evaluation in a chest pain unit (CPU).

Methods: Our study included patients with chest pain at intermediate risk for acute cardiovascular events enrolled in the CHEER study. The primary outcome included a composite of death, myocardial infarction, acute heart failure, stroke, and out-of-hospital cardiac arrest.

Computed tomographic coronary artery calcium assessment for evaluating chest pain in the emergency department: long-term outcome of a prospective blind study.

Objective: To determine the long-term outcome of computed tomographic (CT) quantification of coronary artery calcium (CAC) used as a triage tool for patients presenting with chest pain to an emergency department (ED).

Patients And Methods: Patients (men aged 30-62 years and women aged 30-65 years) with chest pain and low-to-moderate probability of coronary artery disease underwent both conventional ED chest pain evaluation and CT CAC assessment prospectively. Patients' physicians were blinded to the CAC results.

Endothelial function and cardiovascular risk stratification in menopausal women.

Background: Peripheral arterial, endothelium-dependent, flow-mediated reactive hyperemia is reduced in individuals with atherosclerosis. This study tested the hypothesis that digital tonometry, as a surrogate of endothelial function, is useful to stratify cardiovascular risk in recently menopausal women who are asymptomatic for cardiovascular disease.

Methods: Women undergoing screening for the Kronos Early Estrogen Prevention Study (KEEPS) were evaluated for conventional risk factors, flow-mediated reactive hyperemia by digital tonometry (RHI), carotid intima-media thickness (CIMT) by ultrasound, and coronary arterial calcium (CAC) by 64-slice CT scanner.

Characterization of blood borne microparticles as markers of premature coronary calcification in newly menopausal women.

While the risk for symptomatic atherosclerotic disease increases after menopause, currently recognized risk factors do not identify ongoing disease processes in low-risk women. This study tested the hypothesis that circulating cell-derived microparticles may reflect disease processes in women defined as low risk by the Framingham risk score. The concentration and phenotype of circulating microparticles were evaluated in a cross-sectional study of apparently healthy menopausal women, screened for enrollment into the Kronos Early Estrogen Prevention Study.

Pilot study of sex differences in chemokine/cytokine markers of atherosclerosis in humans.

Background: Atherogenic processes increase in women after menopause, when the risk of cardiovascular adverse events approaches that observed in age-matched men. In experimental animals, ovariectomy increases the platelet content of mitogenic cytokines, such as platelet-derived growth factor (PDGF), which when released into the blood or site of vascular injury, contribute to atherogenic processes.

Objective: Experiments were designed to assess the sex distribution of inflammatorychemokines/cytokines, which may be released from platelets in the serum of middle-aged women and men in whom the extent of atherosclerotic coronary disease was defined by coronary arterial calcification (CAC).

Independent association between obstructive sleep apnea and subclinical coronary artery disease.

Background: Obstructive sleep apnea (OSA) is associated with coronary risk factors, but it is unknown if OSA is associated with development of coronary disease. We evaluated the association between OSA and the presence of subclinical coronary disease assessed by coronary artery calcification (CAC).

Methods: Consecutive patients with no history of coronary disease who underwent electron-beam CT within 3 years of polysomnography between March 1991 and December 2003 were included.

Benzocaine-induced methemoglobinemia based on the Mayo Clinic experience from 28 478 transesophageal echocardiograms: incidence, outcomes, and predisposing factors.

Background: The potentially life-threatening condition of methemoglobinemia is characterized by cyanosis, low pulse oximetric readings, and normal arterial Po(2) values. Acquired methemoglobinemia has been linked to the use of the topical anesthetic benzocaine in endoscopic procedures, including transesophageal echocardiography (TEE). Yet, the incidence of benzocaine-induced methemoglobinemia with TEE and the clinical factors associated with its development are unclear.

Left atrial remodelling in mitral regurgitation--methodologic approach, physiological determinants, and outcome implications: a prospective quantitative Doppler-echocardiographic and electron beam-computed tomographic study.

Aims: To define accurate and normal range of echocardiographic left atrial (LA) volume measurement and to assess the prevalence, determinants, and outcome implications of LA enlargement in mitral regurgitation (MR).

Methods And Results: We prospectively compared LA volume obtained simultaneously by electron beam-computed tomography (EBCT) and by four echocardiographic methods in 33 test patients. Accurate echocardiographic LA volume measurements were obtained only by biplane area-length method with vertical longitudinal-length (r = 0.

Secondary hypertension: current diagnosis and treatment.

Secondary hypertension affects a small but significant number of the hypertensive population and, unlike primary hypertension, is a potentially curable condition. The determinant for workup is dependent on the index of suspicion elicited during patient examination and treatment. Specific testing is available and must be balanced depending on the risk and cost of the workup and treatment with the benefits obtained if the secondary cause is eliminated.

Assessment of cardiovascular risk status at CT colonography.

Purpose: To retrospectively determine whether calcium scores of the abdominal aorta obtained during computed tomographic (CT) colonography relate to Framingham risk factors and clinical cardiac events.

Materials And Methods: The institutional review board approved the current HIPAA-compliant retrospective study and waived informed consent. Between 1995 and 1998, 480 patients underwent CT colonography; 467 patients were available for assessment.

Biphasic Doppler pattern of the descending thoracic aorta: a new echocardiographic finding in patients with aortic valve stenosis.

A total of 59 patients (> or = 65 years of age) with normal left ventricular function (ejection fraction > 50%) and varying degrees of aortic valve structure and hemodynamics (normal to severely stenotic) were screened; 50 were subsequently enrolled. Continuous wave Doppler echocardiography in the descending thoracic aorta showed two general patterns: (1) in aortic stenosis, the pattern consisted of two peak systolic velocity components (S1 and S2); and (2) in normal aortic valve function, the pattern was a uniphasic signal with a single peak systolic velocity component. The new Doppler pattern yielded 95% sensitivity and 90% specificity in the detection of clinically significant aortic valve stenosis, and 92% sensitivity and 70% specificity in the detection of severe aortic valve stenosis.

Prevalence and predictors of coronary artery calcification in women with polycystic ovary syndrome.

Polycystic ovary syndrome (PCOS), a common endocrine disorder of reproductive-aged women, is associated with multiple risk factors for coronary heart disease (CHD), such as diabetes mellitus, dyslipidemia, visceral obesity, and hypertension. However, premature coronary atherosclerosis has not been demonstrated in PCOS women. Electron beam computed tomography (EBCT) noninvasively measures coronary artery calcium (CAC), a marker for coronary atherosclerosis.

Intramyocardial blood volume, perfusion and transit time in response to embolization of different sized microvessels.

Objective: To study the role of the coronary microcirculation in response to different-sized microemboli, we measured changes in intramyocardial microvascular blood volume (Bv), perfusion (F) and transit time (TT) and also microvascular patterns of injury.

Methods: Bv, F and TT were quantitated in 24 pigs at baseline and again 2 min after repeat injections of 10- or 100-microm microspheres at rest or during intracoronary adenosine infusion. The association of Bv and TT was assessed in the microsphere pigs and in nine control pigs.

Coronary microvascular functional reserve: quantification of long-term changes with electron-beam CT preliminary results in a porcine model.

Purpose: To evaluate the ability of electron-beam computed tomography (CT) to help quantify long-term changes in coronary microvascular functional reserve in a porcine model.

Materials And Methods: Electron-beam CT-based intramyocardial blood volume and perfusion and Doppler ultrasonography (US)-based intracoronary blood flow were obtained in 13 pigs at baseline and again 3 months later. Measurements were obtained at rest and after the administration of adenosine.

Reproducibility of two coronary calcium quantification algorithms in patients with different degrees of calcification.

Purpose: To evaluate the reproducibility of coronary calcium quantification algorithms by electron beam CT (EBT) in patients with different amounts of calcified plaque using the conventional (Agatston) score and an area score and to demonstrate a potential application of these results for evaluation of follow-up scans.

Methods: In 50 consecutive patients. the conventional calcium score (CCS = Agatston score) and the area score (AS) were summed for each artery and patient.

Evaluation of the coronary venous system using electron beam computed tomography.

New therapeutic strategies in interventional cardiology and electrophysiology involve the coronary veins. This study examines the potential usefulness of electron beam computed tomography to obtain detailed noninvasive definition of the coronary venous anatomy and of arteriovenous relationships. Electron beam computed tomography allows acquisition and three-dimensional reconstruction of tomographic images of the beating heart with high spatial and temporal resolution.

Measurement and display of regional myocardial motion during post infarct treatment.

Quantitative assessment of 3-D regional heart motion has significant potential to provide more specific diagnosis of cardiac malfunction than currently possible. Using functional parametric mapping, regional myocardial motion during a cardiac cycle can be color-mapped onto a deformable heart model to provide better understanding of the structure-to-function relationships in the myocardium, including regional patterns of akinesis or dyskinesis associated with ischemia or infarction. In this study, 3-D reconstructions of human hearts were obtained from Electron-Beam Computed Tomography [1] (EB-CT), comparing stages of treatment after myocardial infarction.