Comparison of Maximal Left Ventricular Intramyocardial Artery Lumen Diameter in 2 Aneurysmectomy Specimen after TMR and 44 Control Patients

Summary TMR (Transmyocardial Laser Revascularization) is of value in angina pectoris not accessible to medication or conventional heart surgery. Therapeutical benefit is thought to be due to patent channels conveying blood from the lumen right into the wall of the left ventricle. Interestingly, histopathological findings of some autopsy patients fail to prove patent laser channels after TMR. We examine histopathological findings of left ventricular aneurysmectomy specimen 7 and 11 months after TMR. We compare the estimated (aneurysmectomy patients) or calculated (44 control patients) Equivalent Value for Left Ventricular Wall Tension (ET) to the Maximal Intramyocardial Artery Lumen Diameter (MIALD). The 44 control patients are selected out of different clinicopathological groups. The ET value is calculated using a simplifying spherical model of the left ventricle, and, like the MIALD value, is based on standardized histological samples of the anterior left ventricular wall and additionally the heart weight. We find an inverse non-linear regressive relationship between ET and MIALD values. This provides a morphologically based model for intramyocardial perfusion, which fits into theoretical physical models, putting the value of the reptile heart theory into question. Additionally it provides first morphological clues that reducing ventricular wall tension actually improves intramyocardial perfusion. We discuss, how the data not fitting into this model represents exceptions, how TMR might provide its beneficial effects, and how its value might be limited by the left ventricular wall tension, and on what basis the mechanism of other procedures such as ventriculectomy (also known as the Batista procedure) and coronary bypass surgery could be compared to our proposed mechanism of the TMR procedure.