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P Soman

Publications and source records attributed to P Soman.

12 recordsLinked to original sources
PubMed2001

Enhanced detection of reversible perfusion defects by Tc-99m sestamibi compared to Tc-99m tetrofosmin during vasodilator stress SPECT imaging in mild-to-moderate coronary artery disease.

OBJECTIVES: We prospectively compared dipyridamole single-photon emission computed tomography (SPECT) imaging with Tc-99m sestamibi and Tc-99m tetrofosmin for the detection of reversible perfusion defects in patients with mild-to-moderate coronary artery disease. BACKGROUND: Tc-99m tetrofosmin has a lower first-pass myocardial extraction fraction compared to Tc-99m sestamibi and thus could underestimate mild perfusion defects. METHODS: Eighty-one patients with 50% to 90% stenosis in one or two major epicardial vessels without previous myocardial infarction, and seven with <5% probability of coronary artery disease underwent dipyridamole SPECT imaging with both agents. The SPECT data were analyzed quantitatively. RESULTS: Tc-99m sestamibi detected reversible perfusion defects in a greater number of segments (total 363 and 285, p < 0.001, and mean +/- SD, 2.2 +/- 3.0 and 1.8 +/- 2.5 per patient, p = 0.008, for Tc-99m sestamibi and Tc-99m tetrofosmin, respectively), demonstrated a larger extent of perfusion defect (mean +/- SD, 15.8% +/- 12.3% and 12.0% +/- 11.4%, p < 0.03, for Tc-99m sestamibi and Tc-99m tetrofosmin, respectively) and more often correctly identified patients with disease in more than one coronary artery (p = 0.02). There was better defect contrast with Tc-99m sestamibi (defect/normal wall count ratios were 0.60 +/- 0.15 vs. 0.73 +/- 0.14 for Tc-99m sestamibi and Tc99m tetrofosmin, respectively, p = 0.01, for reversible defects seen in identical segments with both agents; and 0.73 +/- 0.16 vs 0.79 +/- 0.17, respectively, p <0.01, for reversible defects detected with either agent alone). There was no significant difference in diagnostic sensitivity or image quality. CONCLUSIONS: These differences between two commonly used tracers may have significant diagnostic and prognostic implications.

Adult↗
PubMed2001

Regression of left ventricular remodeling in chronic heart failure: Comparative and combined effects of captopril and carvedilol.

BACKGROUND: This study evaluated the independent and combined effects of captopril and carvedilol on left ventricular remodeling in chronic heart failure. Although angiotensin-converting enzyme inhibitors and b-blockers are known to attenuate the remodeling process in chronic heart failure, a direct comparison of these agents has not been performed. METHODS: We investigated 57 patients with mild to moderate chronic heart failure (48 ischemic, 9 nonischemic) who were randomized in a double-blind fashion to treatment with carvedilol or captopril at maximum doses of 25 mg twice daily for 3 months, followed by 3 months of combined treatment. Serial echocardiography, right heart catheterization, and treadmill exercise testing were performed at baseline, 3 months, and 6 months. After exclusions, 49 patients were evaluated during monotherapy and 48 during combination therapy. RESULTS: Carvedilol monotherapy produced significant reductions in end-systolic volume, leading to a greater median increase in ejection fraction compared with captopril monotherapy (4.7% vs 1.5%, respectively; P <.05). Each drug caused similar reductions in left ventricular mass, chamber sphericity, and pulmonary artery wedge pressure during monotherapy and combined treatment. Adjunctive treatment with carvedilol produced a trend toward a greater increase in ejection fraction (4.3% vs 2.7%, respectively; P not significant) and significantly greater reductions in the wall thickening score index than with captopril (0.25 vs 0.08, respectively; P =.04). CONCLUSIONS: Although angiotensin-converting enzyme inhibitor therapy did not alter left ventricular volume, treatment with carvedilol was associated with reductions in chamber volume; both drugs reduced left ventricular mass and sphericity. These beneficial effects on remodeling may help to explain the relative prognostic benefits of these therapies.

Adrenergic beta-Antagonists↗
PubMed2001

Apical hypertrophic cardiomyopathy: bedside diagnosis by intravenous contrast echocardiography.

Apical cardiomyopathy is rare in the West. The characteristic appearance on left ventriculography has been used to confirm the diagnosis of this condition; transthoracic echocardiography can also be useful in this regard. However, apical artifacts may obscure the typical appearance during echocardiography, and although the advent of tissue harmonic echocardiography has resulted in improved image quality, the technique still may be inadequate in the establishment of a diagnosis. We hypothesized that contrast echocardiography, which improves endocardial border delineation, may be the technique of choice for the diagnosis of apical hypertrophic cardiomyopathy. We report the case of a 40-year-old woman with Down syndrome who had chest pain. The electrocardiogram showed T-wave changes in the lateral precordial leads, but cardiac enzymes were normal. Tissue harmonic echocardiography showed apical akinesia. Intravenous contrast echocardiography, however, revealed typical features of hypertrophic apical cardiomyopathy. Thus contrast echocardiography may be used to establish the diagnosis of this condition.

Adult↗
PubMed2000

Power doppler harmonic imaging: a feasibility study of a new technique for the assessment of myocardial perfusion.

BACKGROUND: The aim of the study was to assess the feasibility of a new technique, power Doppler harmonic imaging (PDHI), for assessing myocardial perfusion through a venous injection of microbubbles, with the use of a new ultrasound contrast agent. METHODS AND RESULTS: Fifteen patients with known coronary artery disease and a resting perfusion abnormality on Tc-99m sestamibi single-photon emission computed tomography (SPECT) underwent PDHI at rest during intravenous injections of 2 to 3 mL of Sonovue (Bracco SpA, Milan, Italy), a new second-generation ultrasound contrast agent. Myocardial perfusion was determined to be present or absent by use of a 5-segment model by 2 blinded observers for both PDHI and SPECT. Of a total of 75 possible myocardial segments, 7 (9%) were not analyzed because of obvious artifacts on PDHI. SPECT showed perfusion defects in 40 of the remaining 68 segments, whereas PDHI showed 39 defects. There was high concordance between the 2 imaging modalities for the presence (93%) as well as the location (96% for the anteroseptal region, 93% for the inferoposterior region, and 87% for the apical region) of the defects. CONCLUSIONS: These preliminary results suggest that PDHI is a feasible technique for the detection of resting myocardial perfusion defects in patients with coronary artery disease after a venous injection of a new second-generation ultrasound contrast agent.

Adult↗
PubMed1999

Improved endocardial visualization with second harmonic imaging compared with fundamental two-dimensional echocardiographic imaging.

BACKGROUND: Endocardial visualization is suboptimal by fundamental imaging in at least 30% of patients. Second harmonic imaging was developed for visualization of myocardial contrast agents. We have hypothesized that endocardial visualization may improve with harmonic imaging compared with fundamental imaging. METHODS AND RESULTS: Accordingly, 40 consecutive patients with poor endocardial visualization by conventional echocardiography in at least 1 left ventricular segment (22-segment model) in the 4 standard views randomly underwent fundamental and harmonic imaging without contrast. The images were separately and randomly analyzed by 2 observers. Endocardial visualization was scored as 0, not visualized; 1, poorly visible; and 2, well visualized. Endocardial visualization indexes were also calculated. More segments were assigned a score of 0 (P <. 001) and 1 (P <.001) by fundamental compared with harmonic imaging, whereas harmonic imaging demonstrated more segments with a score of 2 (P <.001) compared with fundamental imaging. Endocardial visualization indexes were significantly better by harmonic imaging in the parasternal long axis (P <.005), short axis (P <.001), and apical 4- (P <.0001) and 2-chamber views (P <.0001). Similar results were obtained by a second observer. Agreement between the 2 observers regarding improvement, deterioration, or no change in score between harmonic and fundamental imaging was 88% (kappa = 0. 76). Interobserver and intraobserver agreements for systolic wall thickening scores also significantly improved with harmonic compared with fundamental imaging (P <.001). CONCLUSION: Second harmonic imaging is superior to fundamental imaging for endocardial visualization in patients with suboptimal fundamental imaging.

Coronary Disease↗
PubMed1999

Why cardiac magnetic resonance imaging will not make it.

Coronary artery disease is currently the largest killer in the western world, and is estimated to become the leading cause of death worldwide by the year 2020. The question therefore is whether magnetic resonance imaging currently has a place in the already extremely well equipped armamentarium of cardiac testing. Although it is promising, its clinical use is somewhat limited by high cost and low availability of equipment and trained personnel. The absence of portable systems for cardiac application make cardiac magnetic resonance imaging in the emergency room, at the patient's bedside or in the doctor's office impossible. The comparison of the cardiac magnetic resonance imaging with proven and cost-effective techniques like echocardiography and nuclear imaging will be decisive in terms of the choice of imaging modalities in cardiology.

Acute Disease↗
PubMed1997

Prognostic value of dobutamine stress echocardiography in patients undergoing diagnostic coronary arteriography.

There are only a few studies addressing the prognostic value of dobutamine stress echocardiography in patients with suspected coronary artery disease and none have assessed its value compared with coronary arteriography. Accordingly, graded dobutamine stress echocardiography was performed in 121 patients who underwent coronary arteriography based on symptoms and the findings of treadmill exercise electrocardiography. During the follow-up period of mean (SD) months (15 +/- 9) there were 41 cardiac events (death [n = 5], acute myocardial infarction [n = 2], unstable angina [n = 29], and congestive heart failure [n = 5]). There were a greater number of patients with inducible wall motion abnormality (88%) on dobutamine stress with cardiac events compared with those without (55%, p <0.001). The wall motion score indexes at rest (1.6 +/- 0.6) and at peak stress (2.1 +/- 0.8) were worse in patients with cardiac events compared with those without (1.2 +/- 0.3, p <0.001 and 1.5 +/- 0.6, p <0.001, respectively). When multivariate analysis was performed using clinical, exercise, echocardiographic, and coronary arteriographic data the independent predictors of cardiac events were exercise duration (p = 0.01), presence of inducible wall motion abnormality (p = 0.03), and wall motion score index at peak stress (p <0.001). Thus, dobutamine stress echocardiography is a powerful predictor of future cardiac events in patients undergoing exercise testing and coronary arteriography for evaluation of chest pain and is superior to both exercise electrocardiography and coronary arteriography for the prediction of subsequent cardiac events.

Adult↗
PubMed1997

Severe ventricular dysfunction secondary to subarachnoid hemorrhage.

A 39-year-old man was brought to the emergency department in a coma. The electrocardiogram showed partial left bundle-branch block and ST elevation in precordial leads, and serum creatinine kinase activity was elevated. Two-dimensional echocardiography revealed severe biventricular dysfunction. Autopsy demonstrated the presence of subarachnoid hemorrhage. Coronary arteries and the myocardium were macroscopically normal.

Adult↗
PubMedDate not supplied

Inotropic stress with arbutamine is superior to vasodilator stress with dipyridamole for the detection of reversible ischemia with Tc-99m sestamibi single-photon emission computed tomography.

BACKGROUND: There is a paucity of data comparing the relative merits of inotropic and vasodilator stress Tc-99m sestamibi single-photon emission computed tomography (SPECT) for the detection of coronary artery disease and reversible ischemia. METHODS AND RESULTS: Twenty-seven patients referred for diagnostic coronary arteriography underwent separate day dipyridamole and arbutamine Tc-99m sestamibi SPECT imaging with simultaneous two-dimensional echocardiography. The sensitivity of arbutamine and dipyridamole Tc-99m sestamibi for the detection of coronary artery disease was 100% (21 of 21) and 90% (19 of 21), respectively, with a specificity of 66% (4 of 6) for both. Coronary artery disease was detected in all six patients with single vessel disease by both stress modalities. The sensitivity for prediction of multivessel disease was 66% (10 of 15) for arbutamine and 46% (7 of 15) for dipyridamole stress. Arbutamine stress induced a greater extent and severity of perfusion abnormality at peak stress (peak perfusion score 25 +/- 6.2 and 21 +/- 5.9 for arbutamine and dipyridamole, respectively, p = 0.001) and reversible perfusion defects (difference between peak stress and rest scores 8.8 +/- 5.5 and 5.2 +/- 4.4 for arbutamine and dipyridamole, respectively, p = 0.001). Furthermore a significantly higher percentage of reversible defects induced by arbutamine stress was associated with wall thickening abnormality on simultaneous echocardiography, which is a more specific marker of myocardial ischemia (88% and 24% for arbutamine and dipyridamole, respectively, p = 0.002). CONCLUSION: Inotropic stress may be superior to vasodilators for the determination of the extent and severity of myocardial involvement and reversible ischemia by Tc-99m sestamibi SPECT.

Cardiotonic Agents↗
PubMedDate not supplied

The prognostic value of a normal Tc-99m sestamibi SPECT study in suspected coronary artery disease.

BACKGROUND: Myocardial perfusion is widely used for risk stratification of patients with suspected or known coronary artery disease (CAD). Recent years have seen an increasing demand for screening of such patients. The value of a normal stress thallium-201 scanning is well established. The advent of technetium 99m-sestamibi single photon emission computed tomography (SPECT) has enhanced the profile of nuclear cardiology even further as a reliable test for screening. However, in spite of previous reports, there is paucity of large-scale data regarding the prognostic value of a normal Tc 99m-sestamibi scanning result. METHODS: The aim of our study was to assess the incidence of cardiac death and non-fatal myocardial infarction in patients with an intermediate probability of coronary artery disease (CAD). A total of 473 patients with normal stress Tc-99m-sestamibi SPECT were monitored for 30+/-16 (6 to 56) months to assess serious cardiac events. There were 272 men and 201 women, with a mean age of 56+/-2 years, of whom 89% had symptoms suggestive of CAD, 65% had an abnormal exercise electrocardiography, 6% had known CAD, and 5% had a high risk of CAD. The average workload was 9.14 metabolic equivalents, peak exercise heart rate was 93%+/-13% of the age predicted target. RESULTS: The annualized mortality rate was 0.2% (95%CI 0.02% to 0.7%) and no infarctions occurred in this group. CONCLUSIONS: A normal stress Tc-99m-sestamibi is highly predictive of a benign outcome, even in patients with intermediate probability of CAD.

Adult↗