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SummaryUntil the mid-1980s, it was believed that the vectorcardiogram presented a greater specificity, sensitivity and accuracy in comparison to the conventional electrocardiogram, in the diagnosis of the different heart diseases. Recent studies revealed that the vectorcardiogram still is superior to the electrocardiogram in very specific situations, such as in the evaluation of electrically inactive areas, in intraventricular conduction disorders combined and/or in association to inactive areas, in the identification and location of ventricular preexcitation, in the differential diagnosis of patterns varying from normal of electrical axis deviation, in the evaluation of particular aspects of Brugada syndrome, and in the estimation of the severity of some enlargements, among others. With the advent of computerized vectorcardiography, a technology that improves the processing and recording method; a future still promising is expected for this methodology.In the fields of education and research, vectorcardiography provided a better and more rational insight into the electrical phenomena that occurs spatially, and represented an important impact on the progress of electrocardiography. Although a few medical centers still use the method as a routine, we hope that the use of this resource will not get lost over time, since vectorcardiography still represents a source to enrich science by enabling a better morphological interpretation of the electrical phenomena of the heart.

The chronic use of glibenclamide may have mediated the loss of preconditioning benefits in the warm-up phenomenon, probably through its KATP channel-blocker activity, but without acting upon the tolerance to exercise.

Repaglinide, an oral hypoglycemic agent with ATP-sensitive K(+) channel-blocker activity, eliminated the myocardial ischemic preconditioning in patients with coronary disease and diabetes.

OBJECTIVETo assess the effect of two hypoglycemic drugs on ischemic preconditioning (IPC) patients with type 2 diabetes and coronary artery disease (CAD).RESEARCH DESIGN AND METHODSWe performed a prospective study of 96 consecutive patients allocated into two groups: 42 to group repaglinide (R) and 54 to group vildagliptin (V). All patients underwent two consecutive exercise tests (ET1 and ET2) in phase 1 without drugs. In phase 2, 1 day after ET1 and -2, 2 mg repaglinide three times daily or 50 mg vildagliptin twice daily was given orally to patients in the respective group for 6 days. On the seventh day, 60 min after 6 mg repaglinide or 100 mg vildagliptin, all patients underwent two consecutive exercise tests (ET3 and ET4).RESULTSIn phase 1, IPC was demonstrated by improvement in the time to 1.0 mm ST-segment depression and rate pressure product (RPP). All patients developed ischemia in ET3; however, 83.3% of patients in group R experienced ischemia earlier in ET4, without significant improvement in RPP, indicating the cessation of IPC (P < 0.0001). In group V, only 28% of patients demonstrated IPC cessation, with 72% still having the protective effect (P < 0.0069).CONCLUSIONSRepaglinide eliminated myocardial IPC, probably by its effect on the KATP channel. Vildagliptin did not damage this protective mechanism in a relevant way in patients with type 2 diabetes and CAD, suggesting a good alternative treatment in this population.