Biomedical subjects

Mark V Jordan

Publications and source records attributed to Mark V Jordan.

4 recordsLinked to original sources

PubMed2006

Relationship between accurate auscultation of a clinically useful third heart sound and level of experience.

BACKGROUND: Poor performance by physicians-in-training and interobserver variability between physicians have diminished clinicians' confidence in the value of the third heart sound (S3). METHODS: To determine whether auscultation of a clinically useful S3 improves with advancing levels of experience, we performed a prospective, blinded, observational study of 100 patients undergoing left-sided heart catheterization. Patients underwent blinded auscultation by 4 physicians (each from 1 of 4 different levels of experience), phonocardiography, measurement of blood B-type natriuretic peptide levels, echocardiography for measurement of left ventricular ejection fraction, and cardiac catheterization for measurement of left ventricular end-diastolic pressure. RESULTS: Whereas residents' and interns' auscultatory findings demonstrated no significant agreement with phonocardiographic findings, an S3 auscultated by cardiology fellows (kappa = 0.37; P<.001) and cardiology attendings (kappa = 0.29; P = .003) agreed with phonocardiographic findings. Although the sensitivities of the S3 were low (13%-52%) for identifying patients with abnormal measures of left ventricular function, the specificities were high (85%-95%), with the best test characteristics exhibited by phonocardiography and more experienced physicians. The S3 detected by attendings and fellows was superior in distinguishing an elevated B-type natriuretic peptide level, a depressed left ventricular ejection fraction, or an elevated left ventricular end-diastolic pressure (P = .002-.02 for attendings and .02-.03 for fellows) compared with residents (P = .02-.47) or interns (P = .09-.64). CONCLUSIONS: The S3 auscultated by more experienced physicians demonstrated fair agreement with phonocardiographic findings. Although correlations were superior for phonocardiography, the associations between the S3 and abnormal markers of left ventricular function improved with each level of auscultator experience.

Adult↗

PubMed2006

High-sensitivity C-reactive protein and parameters of left ventricular dysfunction.

BACKGROUND: Elevated levels of high-sensitivity C-reactive protein (CRP), an inflammatory marker, have been associated with heart failure. However, it is not known which parameters of left ventricular dysfunction correlate with elevated levels of CRP. METHODS AND RESULTS: In this cross-sectional study of 98 patients referred for cardiac catheterization, we investigated whether commonly used clinical indices of left ventricular dysfunction correlated with CRP levels. CRP levels were elevated to a greater degree in participants with diabetes mellitus (P =.006) and heart failure (P =.003). Increased CRP levels were associated with increased plasma levels of B-type natriuretic peptide (BNP; P =.0001), decreased left ventricular ejection fraction (LVEF; P =.02), and increased left-ventricular end-diastolic pressure (LVEDP; P =.0005). After multivariable adjustment, LVEDP and CRP were independently associated (P =.046). CONCLUSION: CRP is increased in patients with heart failure. Of the clinical parameters of left ventricular dysfunction, direct measurement of left ventricular end-diastolic pressure is most closely associated with CRP.

Aged↗

PubMed2005

Association between phonocardiographic third and fourth heart sounds and objective measures of left ventricular function.

CONTEXT: The third (S3) and fourth (S4) heart sounds detected by phonocardiography are considered to represent the criterion standards of the gallop sounds, but their test characteristics have not been explored. OBJECTIVE: To determine the diagnostic test characteristics of the S3 and S4 for prediction of left ventricular dysfunction using a computerized heart sound detection algorithm. DESIGN, SETTING, AND PARTICIPANTS: Prospective study of 90 adult patients undergoing elective left-sided heart catheterization at a single US teaching hospital between August 2003 and June 2004. The mean age was 62 (SD, 13) years (range, 24-90 years) and 61 (68%) were male. Within a 4-hour period, participants underwent computerized heart sound phonocardiographic analysis, cardiac catheterization, transthoracic echocardiography, and blood sampling for assessment of an S3/S4, left ventricular end-diastolic pressure (LVEDP), left ventricular ejection fraction (LVEF), and B-type natriuretic peptide (BNP), respectively. MAIN OUTCOME MEASURES: Diagnostic test characteristics of the computerized phonocardiographic S3 and S4 using markers of left ventricular function as criterion standards. RESULTS: Mean (SD) LVEDP was significantly elevated (18.4 [6.9] mm Hg vs 12.1 [7.3] mm Hg; P<.001), mean (SD) LVEF was reduced (49.4% [20.2%] vs 63.6% [14.8%]; P<.001), and median (interquartile range) BNP was elevated (330 [98-1155] pg/mL vs 86 [41-192] pg/mL; P<.001) in those with an S3, S4, or both compared with patients without a diastolic heart sound. The sensitivities of these heart sounds to detect an elevated LVEDP, reduced LVEF, or elevated BNP were 41%, 52%, and 32% for an S3, and 46%, 43%, and 40% for an S4, respectively. For abnormal levels of the same markers of ventricular function, the specificities of the S3 were 92%, 87%, and 92%, while the specificities of the S4 were 80%, 72%, and 78%, respectively. CONCLUSIONS: Neither the phonocardiographic S3 nor the S4 is a sensitive marker of left ventricular dysfunction. The phonocardiographic S3 is specific for left ventricular dysfunction and appears to be superior to the moderate specificity of the phonocardiographic S4.

Adult↗

PubMed2005

Effects of intravenous levosimendan on human coronary vasomotor regulation, left ventricular wall stress, and myocardial oxygen uptake.

BACKGROUND: Levosimendan is a calcium-sensitizing agent and an inodilator under current investigation in the treatment of decompensated heart failure. The effects of intravenous levosimendan on the human coronary vasculature, together with myocardial wall stress and oxygen uptake, have not been adequately studied. METHODS AND RESULTS: Ten adult patients underwent right- and left-heart catheterization. Baseline coronary blood flow was determined with quantitative coronary angiography and an intracoronary Doppler-tipped guidewire. Myocardial oxygen uptake was measured with a coronary sinus catheter. Echocardiography was performed before and 30 minutes after an intravenous infusion of levosimendan (24-microg/kg bolus over 10 minutes) was begun. Pulmonary capillary wedge decreased 37% (P=0.009), cardiac output increased 9% (P=0.04), and systemic vascular resistance decreased 18% (P<0.001). Left ventricular ejection fraction increased 20% (P=0.009), and meridional systolic wall stress decreased 48% (P=0.009). Coronary artery diameter increased 10% at 15 minutes (P=0.001) and 11% at 30 minutes (P=0.01). Coronary artery velocity increased 10% over baseline (P=0.04). Coronary blood flow increased 45% (P=0.02), whereas coronary resistance decreased 36% at 30 minutes (P=0.03). Myocardial oxygen extraction decreased 9% at 30 minutes (P=0.04). CONCLUSIONS: Levosimendan given intravenously exerts vasodilator effects on human coronary conductance and resistance arteries. Despite a decrease in coronary perfusion pressure, coronary blood flow is increased. A reduction in coronary vascular resistance and a decrease in coronary venous oxygen content indicate primary coronary vasodilation by levosimendan. Improved left ventricular systolic function and decreased myocardial oxygen extraction suggest improved myocardial efficiency.

Adult↗