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Morton J Kern

Publications and source records attributed to Morton J Kern.

49 records · Page 3Linked to original sources
PubMed2003

Current concepts in coronary physiology for the interventionalist.

Coronary angiography remains the 'gold standard' for the diagnosis of epicardial coronary disease. However, precise quantification of stenosis severity is limited because of the complex three-dimensional geometry of epicardial plaques. To assist the angiographer in lesion assessment, several physiologic measurements have been developed to evaluate stenosis severity, including coronary flow reserve, relative coronary flow reserve and fractional flow reserve. Physiologic lesion assessment can also be an invaluable tool in coronary intervention, evaluating efficacy of angioplasty and stent deployment.

Blood Vessel Prosthesis Implantation↗
PubMed2003

Management of iliac stent movement complicating peripheral vascular intervention: A rescue technique when stent deployment malfunctions.

Percutaneous transluminal peripheral angioplasty (PTA), with and without stenting, has become an effective, accepted, and safe approach for treating intermittent claudication and critical leg ischemia in selected patients. Percutaneous peripheral interventions are subject to complications that require unique solutions when compared to coronary interventions. We report a case of common iliac artery stenting complicated by stent migration and describe an approach to the management of this problem.

Angioplasty, Balloon↗
PubMed2002

Pulse transmission coefficient: a novel nonhyperemic parameter for assessing the physiological significance of coronary artery stenoses.

OBJECTIVES: We sought to test the hypothesis that the pulse transmission coefficient (PTC) can serve as a nonhyperemic physiologic marker for the severity of coronary artery stenosis in humans. BACKGROUND: Coronary lesions may impair the transmission of pressure waves across a stenosis, potentially acting as a low-pass filter. The PTC is a novel nonhyperemic parameter that calculates the transmission of high-frequency components of the pressure signal through a stenosis. Thus, it may reflect the severity of the coronary artery stenosis. This study was designed to examine the correlation between PTC and fractional flow reserve (FFR) in patients with coronary artery disease. METHODS: Pressure signals were obtained by pressure guidewire in 56 lesions (49 patients) in the nonhyperemic state and were analyzed with a new algorithm that identifies the high-frequency components in the pressure signal. The PTC was calculated as the ratio between the distal and proximal high-frequency components of the pressure waveform across the lesion. The FFR measurements were assessed with intracoronary adenosine. RESULTS: There was a significant correlation between PTC and FFR (r = 0.81, p < 0.001). By using a receiver operating characteristic analysis, we identified a PTC < 0.60 (sensitivity 100%, specificity 98%) to be the optimal cutoff value for predicting an FFR < 0.75. CONCLUSIONS: Pulse transmission coefficient is a novel nonhyperemic parameter for the physiologic assessment of coronary artery stenoses. It correlates significantly with FFR and may predict an FFR < 0.75 with high accuracy. Pulse transmission coefficient may be useful as an adjunct measurement to FFR, especially in patients with microcirculatory disease and impaired maximal hyperemia.

Adult↗
PubMed2002

Early changes in coronary flow physiology after balloon angioplasty or stenting: a 24-hour Doppler flow velocity study.

To evaluate early changes in myocardial microcirculation after balloon or stent coronary angioplasty, we studied 57 patients undergoing coronary angioplasty with a Doppler-tipped guidewire, with (n = 26) or without stenting. Postprocedural quantitative coronary angiography and coronary flow velocity were measured after 10 min and 24 hr. As compared to stenting, no stenting was associated with a higher postprocedural stenosis rate (21% +/- 13% vs. 12% +/- 10%; P < 0.05), smaller coronary velocity reserve (CVR; 2.2 +/- 0.4 vs. 2.5 +/- 0.7; P = 0.04), and smaller relative CVR (0.8 +/- 0.2 vs. 1.1 +/- 0.3; P = 0.001). At 24 hr, CVR and relative CVR in the unstented group increased to the level in the stented group, mainly because of a decrease in basal average peak velocity (APV). Overall, there was a significant negative linear relation between CVR and APV variations during the 24-hr period. In the subgroups with persistent abnormalities, CVR variation was closely related to the basal APV/reference APV ratio. In conclusion, coronary reserve normalization can occur within 24 hr after coronary angioplasty and is closely dependent on postangioplasty APV. Myocardial distal resistances should be considered when interpreting postangioplasty CVR.

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