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Kevin C Allman

Publications and source records attributed to Kevin C Allman.

6 recordsLinked to original sources
PubMed2006

Atrial and ventricular echocardiographic correlates of the extent of pulmonary embolism in the elderly.

BACKGROUND: Acute pulmonary thromboembolism (PTE) can be associated with right ventricular (RV) dysfunction. The relative importance of individual echocardiographic parameters, including those suggesting interdependence between right and left heart chambers, in predicting thromboembolic burden in elderly patients with acute PTE is unknown. METHODS: We retrospectively studied the transthoracic echocardiograms of 63 elderly patients (age 71 +/- 16 years) with acute PTE, and assessed which individual echocardiographic parameters identified more than 30% pulmonary artery obstruction on the basis of quantitative ventilation/perfusion pulmonary scintigraphy. RESULTS: RV hypokinesis (visual grade 0-3, P = .02), and the quantitative parameters RV end-systolic area (P = .005) and RV ejection area (P = .01) were associated with more extensive pulmonary artery obstruction. Although right atrial end-systolic area and RV end-diastolic area did not correlate with extent of PTE, the ratio of RV:left ventricular end-diastolic area (P = .003), and ratio of right:left atrial end-systolic area (P = .004), were strongly associated with the extent of pulmonary artery obstruction. These transthoracic echocardiographic parameters were independent of clinical variables such as prior chronic lung disease, congestive cardiac failure, or prior PTE. CONCLUSION: RV systolic dysfunction, RV end-systolic dilatation, right:left atrial end-systolic area ratio, and RV:left ventricular end-diastolic area ratio correlate with extent of PTE in the elderly.

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PubMed2005

The role of left ventricular hypertrophy and diabetes in the presence of transient ischemic dilation of the left ventricle on myocardial perfusion SPECT images.

UNLABELLED: Transient ischemic dilation of the left ventricle found on SPECT myocardial perfusion imaging (MPI) is an accepted marker of severe and extensive coronary artery disease (CAD) and poor prognosis. The influence of other clinical variables on the incidence of transient ischemic dilation is less certain. The aim of this study was to investigate clinical factors that may influence the incidence of transient ischemic dilation. In particular, we looked at factors that may independently affect subendocardial perfusion, such as left ventricular hypertrophy (LVH) and diabetes. METHODS: MPI studies of 103 consecutive patients who had undergone recent coronary angiography (< or =6 mo) and transthoracic echocardiography within a year of stress electrocardiography-gated MPI were retrospectively analyzed. Transient ischemic dilation was assessed quantitatively using a software program. A ratio cutoff of > or =1.22 was considered to represent transient ischemic dilation. Summed stress score and summed difference score (ischemia score) were determined using the standard 17-segment 5-point scoring system to quantify myocardial ischemia. LVH was defined as a left ventricular wall thickness of >11 mm on M-mode echocardiography. Severe CAD was defined as severe stenosis (> or =90%) of either the left anterior descending artery or both the right coronary and lateral circumflex arteries. RESULTS: Nineteen (18%) of the 103 patients had transient ischemic dilation, 19 (18%) had LVH, and 23 (22%) were diabetic. A high percentage had severe CAD (46/103 [45%]), whereas 57 of 103 (55%) had less severe CAD (30/103 [29%]) or nonsignificant CAD (26/103 [25%]). Severe CAD (P < 0.001), diabetes (P < 0.0001), LVH (P < 0.003), and the ischemia score (P < 0.023) were independent predictors of transient ischemic dilation by multivariate logistic regression. In patients with severe CAD, the effect of LVH on the incidence of transient ischemic dilation was additive, increasing the incidence from 21% (8/38) without LVH to 75% (6/8) with LVH (P < 0.006). Likewise, with severe CAD, the incidence of transient ischemic dilation rose from 21% (7/33) in patients without diabetes to 54% (7/13) in those with diabetes (P < 0.04). CONCLUSION: The presence of transient ischemic dilation on myocardial perfusion SPECT is associated with the presence of severe CAD, but this association is modified by the presence of LVH and diabetes.

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PubMed2002

Myocardial viability testing and impact of revascularization on prognosis in patients with coronary artery disease and left ventricular dysfunction: a meta-analysis.

OBJECTIVES: This study pools data from published series examining late survival with revascularization versus medical therapy after myocardial viability testing in patients with severe coronary artery disease (CAD) and left ventricular (LV) dysfunction. BACKGROUND: Previous observational studies have suggested survival benefit in such patients if they are revascularized when myocardial viability is detected on imaging tests. METHODS: A MEDLINE database search returned 24 viability studies reporting patient survival using thallium perfusion imaging, F-18 fluorodeoxyglucose metabolic imaging or dobutamine echocardiography. Annual death rates were extracted, pooled and analyzed with a random effects model. The risk-adjusted relationship between severity of LV dysfunction, presence of viability and survival benefit associated with revascularization was assessed by meta-regression. RESULTS: There were 3,088 patients (2,228 men), ejection fraction 32 +/- 8%, followed for 25 +/- 10 months. In patients with viability, revascularization was associated with 79.6% reduction in annual mortality (16% vs. 3.2%, chi-square = 147, p < 0.0001) compared with medical treatment. Patients without viability had intermediate mortality, trending to higher rates with revascularization versus medical therapy (7.7% vs. 6.2%, p = NS). Patients with viability showed a direct relationship between severity of LV dysfunction and magnitude of benefit with revascularization (p < 0.001). There was no measurable performance difference for predicting revascularization benefit between the three testing techniques. CONCLUSIONS: This meta-analysis demonstrates a strong association between myocardial viability on noninvasive testing and improved survival after revascularization in patients with chronic CAD and LV dysfunction. Absence of viability was associated with no significant difference in outcomes, irrespective of treatment strategy.

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