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We present a comprehensive methodology for the electrodynamic modeling of substrate noise coupling. A new and efficient method is introduced for the calculation of the Green's function that can accommodate arbitrary substrate doping profiles and thus facilitate substrate noise analysis using boundary element methods. In addition to a discussion of the application of the method and its validation in the context of substrate transfer resistance extraction, preliminary results from its application to frequency-dependent substrate noise modeling are presented also.

Background: Ischemic cardiomyopathy can be the result of large or small my‐ocardial infarctions or due to myocardial hibernation. Patients with an end‐systolic volume index >100 mL/m2 do not benefit from revascularization alone and require an operation that reduces ventricular volume. Various approaches to reduce ventricular volume have been described. We applied several of these techniques in patients with end‐stage ischemic cardiomyopathy. Methods: Forty eight patients with end‐stage ischemic cardiomyopathy (Class III‐IV) underwent left ventricular volume reduction operations with coronary revascularization and mitral valve repair or Alfieri valvoplasty. Fourteen patients underwent interpapil‐lary resections, 22 anterior resections, 4 posterior resections, 2 anterior and posterior resections, and 6 patients reduction of left ventricular volume with endocavitary patches. Results: All the techniques used improved left ventricular function. Analysis of mortality revealed that extensive resections (interpapillary, anterior, and posterior resection) had a 43% mortality. However, a limited resection or a ventricular reconstruction with an endocavitary patch had only a 12.5% mortality. When we changed our approach to a more conservative one, mortality was reduced from 26% the first 12 months to 13% in the last 15 months of the study. Conclusions: Ischemic cardiomyopathy has a poor prognosis if the end‐systolic volume index exceeds 100 mL/m2. Various procedures exist to reduce left ventricular volume. Extensive ventricular resections improve ventricular function, but have a high mortality. This led us to use other methods of ventricular volume reduction such as more conservative resections combined with left ventricular reconstructions or ventricular volume reduction with endocavitary patches. Mortality was reduced significantly by this approach. The patients that survived have remained Class I‐II in a follow‐up that extends up to 30 months. Surgical therapy of Class III‐IV ischemic cardiomyopathy is feasible, but aggressive ventricular resections have a high mortality. We advocate a more reconstructive approach with limited or no ventricular resection.