Avaliação prognóstica da doença coronária estável através de um novo escore / New prognostic score for stable coronary disease evaluation / Evaluación pronóstica de la enfermedad coronaria estable a través de un nuevo score

FUNDAMENTO: A necessidade de melhorar a acurácia do teste de esforço, determinou o desenvolvimento de escores, cuja aplicabilidade já foi amplamente reconhecida. OBJETIVO: Avaliação prognóstica do coronariopata estável através de um novo escore simplificado. MÉTODOS: Um novo escore foi aplicado em 372 coronariopatas multiarteriais e função ventricular preservada, 71,8 por cento homens, idade média 59,5 (± 9,07) anos, randomizados para angioplastia, revascularização cirúrgica e tratamento clínico, acompanhados por 5 anos. Óbito cardiovascular foi o desfecho primário. Infarto do miocárdio não-fatal, óbito e re-intervenção formaram o desfecho combinado secundário. O escore baseou-se numa equação previamente validada resultante da soma de 1 ponto para: sexo masculino, história de infarto, angina, diabete, uso de insulina e ainda 1 ponto para cada década de vida a partir dos 40 anos. Teste positivo adicionou 1 ponto. RESULTADOS: Ocorreram 36 óbitos (10 no grupo angioplastia, 15 no grupo revascularização e 11 no grupo clínico), p = 0,61. Observou-se 93 eventos combinados: 37 no grupo angioplastia, 23 no grupo revascularização e 33 no grupo clínico (p = 0,058). 247 pacientes apresentaram escore clínico > 5 pontos e 216 > 6 pontos. O valor de corte > 5 ou > 6 pontos identificou maior risco, com p = 0,015 e p = 0,012, respectivamente. A curva de sobrevida mostrou uma incidência de óbito após a randomização diferente naqueles com escore > 6 pontos (p = 0,07), e uma incidência de eventos combinados diferente entre pacientes com escore < 6 e > 6 pontos (p = 0,02). CONCLUSÃO: O novo escore demonstrou consistência na avaliação prognóstica do coronariopata estável multiarterial.

BACKGROUND: The need to improve the exercise testing accuracy, pushed the development of scores, whose applicability was already broadly recognized. OBJECTIVE: Prognostic evaluation of stable coronary disease through a new simplified score. METHODS: A new score was applied in 372 multivessel coronary patients with preserved ventricular function, 71.8 percent male, age: 59.5 (± 9.07) years old, randomized to medical treatment, surgery (CABG) or angioplasty (PTCA), with 5 years of follow-up. Cardiovascular death was considered the primary endpoint. Non-fatal myocardial infarction, death and re-intervention were considered for a combined secondary endpoint. The score was based on an equation previously validated, resulting from a sum of one point for: male gender, infarction history, angina, diabetes, insulin use and one point for each decade of life after 40 years old. Positive exercise testing summed one additional point. RESULTS: Thirty six deaths was observed (10 in group PTCA, 15 in CABG and 11 in the clinical group), p = 0.61. We observed 93 combined events: 37 in PTCA group, 23 in CABG and 33 in the clinical group (p = 0.058). 247 patients presented clinical score > 5 points and 216 > 6 points. The cutoff point > 5 or > 6 points identified higher risk, p = 0.015 and p = 0.012, respectively. The survival curve showed a different death incidence after the randomization when score reached 06 points or more (p = 0.07), and a distinct incidence of combined events between the patients with score < 6 and > 6 points (p = 0.02). CONCLUSION: The new score was consistent for multiarterial stable coronary disease risk stratification.

FUNDAMENTO: La necesidad de mejorar la exactitud de las pruebas de estrés, determinó el desarrollo de los puntajes, cuya aplicación fue ampliamente reconocida. OBJETIVO: La evaluación pronóstica del coronariópata estable a través de un nuevo score simplificado. MÉTODOS: Un nuevo score se aplicó en 372 coronariópatas multiarteriales y función ventricular preservada, el 71,8 por ciento varones, edad media de 59,5 (± 9,07) años, randomizados para angioplastia, revascularización quirúrgica y tratamiento clínico, seguidos de cinco años. Muerte cardiovascular fue el resultado primario. El infarto de miocardio no fatal, la muerte y la re-intervención formaron el desenlace combinado secundario. El score se basó en una ecuación previamente validada resultante de la suma de 1 punto a: sexo masculino, antecedentes de infarto, angina, diabetes, uso de insulina y todavía un punto por cada década de vida después de 40 años. Prueba positiva añadida 1 punto. RESULTADOS: Hubo 36 muertes (10 en el grupo de angioplastia, 15 en el grupo de revascularización y 11 en el grupo clínico), p = 0,61. Se observó 93 eventos combinados: 37 en el grupo angioplastia, 23 en el grupo revascularización y 33 en el grupo clínico (p = 0,058). Presentaron score clínico > 5 puntos y 216 > 6 puntos 247 pacientes. El valor de corte > 5 o > 6 puntos identificó un mayor riesgo, con p = 0,015 y p = 0,012, respectivamente. La curva de sobrevida mostró una incidencia de muerte después de la aleatorización que aquellos con score > 6 puntos (p = 0,07), y una incidencia de eventos combinados diferentes entre los pacientes con score < 6 y > 6 puntos (p = 0,02). CONCLUSIÓN: El nuevo score demostró consistencia en la evaluación pronóstica del coronariópata estable multiarterial. (Arq Bras Cardiol 2011;96(5):411-419).

Electrovectorcardiographic diagnosis of left septal fascicular block: anatomic and clinical considerations.

Several publications considering anatomical, histological, pathological, electrocardiographic, vectorcardiographic, and electrophysiologic studies have shown that the left bundle branch splits into three fascicles or in a "fan-like interconnected network" in the vast majority of human hearts. The left His system is trifascicular with a left anterior, a left posterior, and a left septal fascicle (LSF). Consequently, the classic term "hemiblock," to describe the block of one of the fascicles, established several decades ago by the Rosembaum's school, should be updated. Electrovectorcardiographic changes resulting from conduction abnormalities of the left anterior and left posterior fascicles are commonly diagnosed, mainly by their changes in the frontal plane. However, the existence of conduction defects of the LSF remains controversial. The ECG/VCG hallmark of LSF block is prominent anterior QRS forces (PAF) on the horizontal plane. This ECG/VCG phenomena should be distinguished from other conditions that also produce anterior QRS shift in the HP as: normal variants, right ventricular enlargement, misplaced precordial leads, lateral myocardial infarction, right bundle branch block, Wolff-Parkinson-White, obstructive and nonobstructive forms of hypertrophic cardiomyopahty, diastolic left ventricular enlargement, endomiocardial fibrosis, Duchenne muscular dystrophy, and dextroposition. The two highly frequent etiologies of LSFB are ischemia (coronary artery disease (CAD) with critical proximal obstruction of the left anterior descending coronary artery) and, in Latin America, Chagas' cardiomyopathy. The aims of this review are to revise the evidence of the existence of a trifascicular left Hissian system and to help in the ECG/VCG recognition of the LSFB.

New prognostic score for stable coronary disease evaluation.

BACKGROUND: The need to improve the exercise testing accuracy, pushed the development of scores, whose applicability was already broadly recognized. OBJECTIVE: Prognostic evaluation of stable coronary disease through a new simplified score. METHODS: A new score was applied in 372 multivessel coronary patients with preserved ventricular function, 71.8% male, age: 59.5 (± 9.07) years old, randomized to medical treatment, surgery (CABG) or angioplasty (PTCA), with 5 years of follow-up. Cardiovascular death was considered the primary endpoint. Non-fatal myocardial infarction, death and re-intervention were considered for a combined secondary endpoint. The score was based on an equation previously validated, resulting from a sum of one point for: male gender, infarction history, angina, diabetes, insulin use and one point for each decade of life after 40 years old. Positive exercise testing summed one additional point. RESULTS: Thirty six deaths was observed (10 in group PTCA, 15 in CABG and 11 in the clinical group), p = 0.61. We observed 93 combined events: 37 in PTCA group, 23 in CABG and 33 in the clinical group (p = 0.058). 247 patients presented clinical score ≥ 5 points and 216 ≥ 6 points. The cutoff point ≥ 5 or ≥ 6 points identified higher risk, p = 0.015 and p = 0.012, respectively. The survival curve showed a different death incidence after the randomization when score reached 06 points or more (p = 0.07), and a distinct incidence of combined events between the patients with score < 6 and ≥ 6 points (p = 0.02). CONCLUSION: The new score was consistent for multiarterial stable coronary disease risk stratification.

Escore eletrocardiográfico: aplicação em ergometria para avaliação do precondicionamento isquêmico / Electrocardiographic score: application in exercise test for the assessment of ischemic preconditioning / Escore electrocardiográfico: aplicación en ergometría para evaluación del preacondicionamiento isquémico

FUNDAMENTO: O tempo para 1,0 mm de depressão do segmento ST (T-1,0 mm), adotado para caracterizar o precondicionamento isquêmico (PCI) em testes ergométricos sequenciais, é consistente e reprodutível, porém, possui várias limitações. OBJETIVO: Aplicar um escore eletrocardiográfico de isquemia miocárdica em testes ergométricos sequenciais, comparando-o com o clássico índice T-1,0 mm. MÉTODOS: Avaliamos 61 pacientes, com idade média de 62,2 ± 7,5 anos, sendo 86,9 por cento homens. Foram analisados 151 exames, sendo 116 de pacientes que completaram duas fases de avaliação. A primeira fase compreendia dois testes ergométricos sequenciais para documentação do PCI e a segunda fase, após uma semana, mais dois testes sob efeito de repaglinida. Dois observadores aplicaram o escore de forma cega. RESULTADOS: Observou-se concordância perfeita inter e intraobservador (Kendall Tau-b = 0,96, p < 0,0001, Kendall Tau-b = 0,98,p < 0,0001, respectivamente). Os valores de sensibilidade, especificidade, valor preditivo negativo, valor preditivo positivo e acurácia foram de 72,41 por cento, 89,29 por cento, 75,8 por cento, 87,5 por cento e 81,0 por cento, respectivamente. CONCLUSÃO: O escore de isquemia é um método consistente e reprodutível para documentação do PCI, representando uma alternativa factível ao índice T-1,0 mm.

BACKGROUND: The time for 1.0 mm ST-segment depression (T-1.0mm) adopted to characterize ischemic preconditioning (IPC) in sequential exercise tests is consistent and reproducible; however, it has several limitations. OBJECTIVE: To apply an electrocardiographic score of myocardial ischemia in sequential exercise tests, comparing it to the conventional T-1.0 mm index. METHODS: Sixty one patients with mean age of 62.2 ± 7.5 years were evaluated; 86.9 percent were males. A total of 151 tests were analyzed, 116 of which were from patients who completed two assessment phases. The first phase comprised two sequential exercise tests for the documentation of IPC; the second phase, initiated one week later, comprised two more tests carried out under the effect of repaglinide. Two observers who were blind to the tests applied the score. RESULTS: Perfect inter and intraobserver agreement was found (Kendall tau-b = 0.96, p < 0.0001, and Kendall tau-b = 0.98, p < 0.0001, respectively). Values of sensitivity and specificity, negative predictive value, positive predictive value and accuracy were 72.41 percent, 89.29 percent, 75.8 percent, 87.5 percent and 81.0 percent, respectively. CONCLUSION: The ischemic score is a consistent and reproducible method for the documentation of IPC, and is a feasible alternative to T-1.0 mm.

FUNDAMENTO: El tiempo para 1,0 mm de depresión del segmento ST (T-1,0 mm), adoptado para caracterizar el preacondicionamiento isquémico (PCI) en test ergométricos secuenciales, es consistente y reproducible, sin embargo, posee varias limitaciones. OBJETIVO: Aplicar un escore electrocardiográfico de isquemia miocárdica en test ergométricos secuenciales, comparándolo al clásico índice T-1,0 mm. MÉTODOS: Evaluamos 61 pacientes, con edad media de 62,2 ± 7,5 años, siendo 86,9 por ciento hombres. Fueron analizados 151 exámenes, siendo 116 de pacientes que completaron dos fases de evaluación. La primera fase comprendía dos test ergométricos secuenciales para documentación del PCI y la segunda fase, después de una semana, más dos test bajo efecto de repaglinida. Dos observadores aplicaron el escore de forma ciega. RESULTADOS: Se observó concordancia perfecta inter y intraobservador (Kendall Tau-b = 0,96, p < 0,0001, Kendall Tau-b = 0,98,p < 0,0001, respectivamente). Los valores de sensibilidad, especificidad, valor predictivo negativo, valor predictivo positivo y precisión fueron de 72,41 por ciento, 89,29 por ciento, 75,8 por ciento, 87,5 por ciento y 81,0 por ciento, respectivamente. CONCLUSIÓN: El escore de isquemia es un método consistente y reproducible para documentación del PCI, representando una alternativa factible al índice T-1,0 mm.

[Electrocardiographic score: application in exercise test for the assessment of ischemic preconditioning]. / Escore eletrocardiográfico: aplicação em ergometria para avaliação do precondicionamento isquêmico.

BACKGROUND: the time for 1.0 mm ST-segment depression (T-1.0mm) adopted to characterize ischemic preconditioning (IPC) in sequential exercise tests is consistent and reproducible; however, it has several limitations. OBJECTIVE: to apply an electrocardiographic score of myocardial ischemia in sequential exercise tests, comparing it to the conventional T-1.0 mm index. METHODS: sixty one patients with mean age of 62.2 ± 7.5 years were evaluated; 86.9% were males. A total of 151 tests were analyzed, 116 of which were from patients who completed two assessment phases. The first phase comprised two sequential exercise tests for the documentation of IPC; the second phase, initiated one week later, comprised two more tests carried out under the effect of repaglinide. Two observers who were blind to the tests applied the score. RESULTS: Perfect inter and intraobserver agreement was found (Kendall tau-b = 0.96, p < 0.0001, and Kendall tau-b = 0.98, p < 0.0001, respectively). Values of sensitivity and specificity, negative predictive value, positive predictive value and accuracy were 72.41%, 89.29%, 75.8%, 87.5% and 81.0%, respectively. CONCLUSION: the ischemic score is a consistent and reproducible method for the documentation of IPC, and is a feasible alternative to T-1.0 mm.

Aspectos básicos da ergometria contemporânea / Basics of contemporary exercise testing

O teste ergométrico é um exame já bem estabelecido e vem sendo adotado na prática clínica por várias décadas. Ele é geralmente seguro, mas deve ser considerado de forma judiciosa, indicando-se de forma apropriada qual o tipo de paciente que deve ser submetido ao exame. A interpretação do teste ergométrico inclui capacidade funcional, aspectos clínicos, hemodinâmicos e a resposta eletrocardiográfica...

Exercise testing is a well-established procedure that has been in widespread clinical use for many decades. Exercise testing is generally a safe procedure, but good clinical judgment should therefore be used in deciding which patients should undergo exercise testing. Interpretation of the exercise test should include exercise capacity and clinical, hemodynamic, and electrocardiographic response...

Wellens syndrome associated with prominent anterior QRS forces: an expression of left septal fascicular block?

Wellens syndrome is a clinical-electrocardiographic entity also referred to as left anterior descending (LAD) coronary T-wave syndrome or acute coronary T-wave syndrome. It is a complex of symptoms and signals indicating the existence of an undesirable condition secondary to critical high-grade proximal stenosis of the LAD coronary artery characterized by the association of prior history of acute coronary syndrome with little or no elevation of markers of myocardial damage (unstable angina) and characteristic electrocardiographic changes consistent with subepicardial anterior ischemic pattern (persistently symmetrical, deep negative and broad-based T waves) or plus-minus T waves with inversion of the terminal portion in the LAD coronary artery territory (V1 through V5 or V6). We present a case of a variant of Wellens syndrome that reveals association and, transitorily, the criteria described in literature for left septal fascicular block.

Relationship among amiodarone, new class III antiarrhythmics, miscellaneous agents and acquired long QT syndrome.

Class III drugs prolong the QT interval by blocking mainly the delayed rectifier rapid potassium outward current (IKr), with little effect on depolarization. This K(+) channel in encoded by the human ether-a-go-go-related gene (hERG). Inhibition of hERG potassium currents by class III antiarrhythmic drugs causes lengthening of cardiac action potential, which produces a beneficial antiarrhythmic effect. Excessive prolongation of the action potential may lead to acquired long QT syndrome, which is associated with a risk of "torsade de pointes". Class III agents can block all types of potassium channels: IKs, IKr, IKur and IK1. The main representing class III agent is amiodarone. It is the gold standard in the prevention of recurrence of atrial fibrillation. Although it is highly effective in treating many arrhythmias, large number of adverse effects limits its clinical use. Dronedarone is a synthetic amiodarone analogue, iodine-free compound, with fewer adverse effects, and shares amiodarone's multichannel blocking effects, inhibiting transmembrane Na+, IKs, IKur, IK1, and slow Ca(++)L-type calcium currents. The main new generation class III drugs are: dofetilide, dronedarone, azimilide, and ibutilide. Oral dofetilide did not increase mortality in patients with a recent myocardial infarction or congestive heart failure. It is an alternative for the pharmacological conversion of atrial fibrillation and flutter. Azimilide blocks both rapid and slow potassium channels components. Azimilide is not a methanesulfonanilide compound. Trecitilide, tedisamil, ersentilide, ambasilide, chromanol and sematilide are class III miscellaneous agents. Old mixed agents are sotalol and bretylium. The present article reviews the main trials accomplished with these drugs.

The history of left septal fascicular block: chronological considerations of a reality yet to be universally accepted.

There are several papers in literature that prove in a conclusive and incontestable way, that the left branch of the His bundle, in most instances (85% of the cases) splits into three fascicles of variable morphological pattern, and not into two: left anterior fascicle (LAF), left posterior fascicle (LPF), and left septal fascicle (LSF). The abovementioned papers have anatomical, histological, anatomo-pathological, electrocardiographic, and vectocardiographic, body surface potential mapping or ECG potential mapping and electrophysiological foundation.Additionally, the mentioned papers have been performed both in animal models (dogs) and in the human heart.Several clinical papers have shown that the left septal fascicular block (LSFB) may occur intermittently or transitorily as a consequence of a temporary dromotropic alteration, constituting an aberrant ventricular conduction, rate-dependent or by the application of atrial extra-stimuli, or naturally during the acute phase of infarction when this involves the anterior descending artery, before the septal perforating artery that supplies the central portion of the septum, where the mentioned LSF runs.The ECG/VCG manifestation of LSFB consists in anterior shift of electromotive forces, known as Prominent Anterior Forces (PAF), which can hardly be diagnosed in the clinical absence of other causes capable of causing PAF, such as the normal variant by counterclockwise rotation of the heart on its longitudinal axis, in right ventricular enlargement, in the dorsal or lateral infarction of the new nomenclature, in type-A WPW, in CRBBB, and others. In this historical manuscript, we review in a sequential fashion, the main findings that confirmed the unequivocal existence of this unjustifiably "forgotten" dromotropic disorder.In the developed countries, its most important cause is coronary insufficiency, particularly the proximal involvement of the left anterior descending coronary artery, and in Latin America, Chagas disease.

Significance of vectorcardiogram in the cardiological diagnosis of the 21st century.

Until 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.

Radiofrequency catheter ablation of premature ventricular contractions originating in the right ventricular outflow tract.

OBJECTIVES: To evaluate if radiofrequency catheter ablation is an effective procedure for the treatment of right ventricular outflow tract premature ventricular contractions (RVOT-PVC) and ascertain if it results in an improvement of symptoms. METHODS: A prospective study with 30 consecutive patients (mean age 40 +/- 13 years, 25 females), with no apparent structural cardiopathy, with very frequent (mean density of 1,263 +/- 593/h) RVOT-PVC, symptomatic for more than one year (mean = 74 months) and resistant to antiarrhythmic drugs (3 +/- 1.7, including beta-blockers), who underwent radiofrequency catheter ablation. RESULTS: After the first procedure, there were 23 initial successful cases (76.6%) and 7 initial failures (23.4%). Four patients experienced relapses, two of whom did not undergo the second procedure. The second procedure was carried out in 9 patients (7 initial failures and 2 relapses), and there was success in 5 additional patients, one of them by epicardial access. The final success rate was 80% (24/30), and there were no major complications. After a mean follow-up of 14 +/- 6 months, in the successful group there was a reduction greater than 90% in density of premature ventricular contractions (PVC) (24/24; p<0.0001) and a resulting absence of symptoms in the majority of patients (23/24; p<0.001). CONCLUSION: Radiofrequency catheter ablation is a safe and effective treatment for patients with persistent and symptomatic PVC with RVOT morphology.

Ablação com radiofreqüência de extra-sístoles da via de saída do ventrículo direito / Radiofrequency catheter ablation of premature ventricular contractions originating in the right ventricular outflow tract

OBJETIVOS: Avaliar se a ablação com radiofreqüência é um procedimento eficiente para o tratamento das extra-sístoles da via de saída do ventrículo direito (EVSVD), e se resulta em melhora dos sintomas. MÉTODOS: Estudo prospectivo, com 30 pacientes consecutivos (idade média de 40±13 anos, 25 do sexo feminino), sem cardiopatia estrutural aparente, com EVSVD, muito freqüentes (densidade média de 1.263±593/h), sintomáticos por mais de 1 ano (média =74 meses) e refratários aos fármacos antiarrítmicos (3±1,7, incluindo os beta-bloqueadores), que foram submetidos à ablação com radiofreqüência. RESULTADOS: Após o primeiro procedimento, houve 23 sucessos iniciais (76,6 por cento) e 7 iniciais insucessos (23,4 por cento). Quatro pacientes tiveram recorrências, sendo que dois desses não se submeteram ao segundo procedimento. O segundo procedimento foi realizado em 9 pacientes (7 insucessos iniciais e 2 recorrências), e o sucesso ocorreu em 5 pacientes adicionais, sendo 1 caso por acesso epicárdico. A taxa de sucesso final foi de 80 por cento (24/30), e nenhuma complicação maior ocorreu. Após um seguimento médio de 14±6 meses, no grupo de sucesso final houve uma redução de mais de 90 por cento na densidade das extra-sístoles(24/24; p<0,0001) e resultante ausência de sintomas na maioria dos pacientes (23/24; p<0,001). CONCLUSÃO: A ablação com radiofreqüência é um tratamento seguro e eficaz para os pacientes com extra-sístoles persistentes e sintomáticas com morfologia do trato de saída do ventrículo direito.

OBJECTIVES: To evaluate if radiofrequency catheter ablation is an effective procedure for the treatment of right ventricular outflow tract premature ventricular contractions (RVOT-PVC) and ascertain if it results in an improvement of symptoms. METHODS: A prospective study with 30 consecutive patients (mean age 40 ± 13 years, 25 females), with no apparent structural cardiopathy, with very frequent (mean density of 1,263 ± 593/h) RVOT-PVC, symptomatic for more than one year (mean = 74 months) and resistant to antiarrhythmic drugs (3 ± 1.7, including beta-blockers), who underwent radiofrequency catheter ablation. RESULTS: After the first procedure, there were 23 initial successful cases (76.6 percent) and 7 initial failures (23.4 percent). Four patients experienced relapses, two of whom did not undergo the second procedure. The second procedure was carried out in 9 patients (7 initial failures and 2 relapses), and there was success in 5 additional patients, one of them by epicardial access. The final success rate was 80 percent (24/30), and there were no major complications. After a mean follow-up of 14 ± 6 months, in the successful group there was a reduction greater than 90 percent in density of premature ventricular contractions (PVC) (24/24; p<0.0001) and a resulting absence of symptoms in the majority of patients (23/24; p<0.001). CONCLUSION: Radiofrequency catheter ablation is a safe and effective treatment for patients with persistent and symptomatic PVC with RVOT morphology.

Effect of a hypoglycemic agent on ischemic preconditioning in patients with type 2 diabetes and stable angina pectoris.

OBJECTIVE: Ischemic preconditioning is an increased tolerance to myocardial ischemia during the second of two consecutive exercise tests. ATP-sensitive K(+) channel blockers, such as glinides and sulfonylurea drugs, can induce loss of ischemic preconditioning. This study aimed to investigate the effects of repaglinide, a hypoglycemic agent with an affinity for myocardial ATP-sensitive K (+)channels, on the results of consecutive exercise tests in patients with diabetes and multivessel coronary artery disease. METHODS: Forty-two patients with type 2 diabetes and chronic stable angina pectoris, and two-vessel or three-vessel disease participated in this study. The patients underwent two consecutive treadmill exercise tests (phase 1). On the day after these exercise tests, 2 mg of oral repaglinide was given to the patients. One week later, two exercise tests were repeated consecutively (phase 2). RESULTS: All patients achieved 1.0-mm ST-segment depression during the four exercise tests (T1, T2, T3, and T4). In phase 2, seven patients improved in time to onset of 1.0-mm ST-segment depression. The worsening of the time to onset of 1.0-mm ST-segment depression in phase 2 demonstrated ischemic preconditioning block in 83.3% of patients (P=0.0001). Even the postexercise electrocardiographic parameters (ST-segment depression morphology and magnitude and arrhythmias) were significantly different between the groups with and without pharmacologic ischemic preconditioning block (P=0.031). CONCLUSIONS: Repaglinide, an oral hypoglycemic agent with ATP-sensitive K(+) channel-blocker activity, eliminated the myocardial ischemic preconditioning in patients with coronary disease and diabetes.