Remote ischemic postconditioning: does it protect against ischemic damage in percutaneous coronary revascularization? justification and design of a randomized placebo-controlled clinical trial.

OBJECTIVE: Myocardial damage that is associated with percutaneous coronary intervention (PCI) partially affects the results of the procedure, and is related to medium-term cardiovascular death. Remote postischemic conditioning might reduce the myocardial lesions that are associated with PCI, but perhaps less so in diabetics. The aim of this study was to evaluate the protective effect of remote postischemic conditioning in patients undergoing elective PCI for stable angina or non-ST elevation acute coronary syndrome with troponin <1 ng/ml at the time of randomization. METHODS: This randomized single-blinded single-center clinical trial involved 320 patients undergoing elective PCI who were randomized to either receive three 5-min cycles of ischemia by inflation of a cuff on the non-dominant arm to 200 mm Hg (remote postischemic conditioning) or to placebo (uninflated cuff). The primary outcome variable was the maximum increase in troponin in the first 24 h. The secondary outcome variable was readmission due to heart failure or cardiovascular mortality after 1 year of follow-up. In addition, a diabetic population was studied. CONCLUSIONS: This clinical trial evaluated the possible reduction in intervention-related myocardial damage that was attributable to remote postischemic conditioning.

[The influence of angina the week before a first myocardial infarction on short and medium-term prognosis]. / Influencia de la angina en la semana previa al primer infarto agudo de miocardio sobre su pronóstico intrahospitalario y a medio plazo.

INTRODUCTION AND OBJECTIVES: The implications of early angina on the prognosis of myocardial infarction are controversial. The aim of this study was to assess the effect of angina one week before the first myocardial infarction on short and medium-term prognosis. PATIENTS AND METHOD: A total of 290 consecutive patients (107 with previous angina and 183 without it) with the first myocardial infarction were studied to determine the effect of preceding angina on short and medium-term prognosis. Further criteria for inclusion were no previous history of angina > 1 week before the first myocardial infarction, and no evidence of prior structural cardiopathy. The end points studied were death and congestive heart failure in the acute phase of myocardial infarction and during the follow-up. RESULTS: Patients with a history of prodromal angina were less likely to experience in-hospital death, heart failure or combined end-point (3.7 vs 11.5%; 4.6 vs 15.8%; 7.5 vs 21.3%) (p = 0.002). There was also a difference between groups in the follow-up (4.1 vs 13.2%; p = 0.03). Multivariate analysis confirmed that the presence of preinfarction angina was an independent predictor of death and heart failure in the acute phase of myocardial infarction as well as in the follow-up. CONCLUSIONS: The occurrence of angina one week before the first myocardial infarction protects against death and heart failure in the acute phase of myocardial infarction as well as in the medium follow-up.

[Creatine kinase increases after coronary interventions]. / Elevaciones de la creatincinasa tras intervencionismo coronario.

INTRODUCTION AND OBJECTIVES: Percutaneous revascularization has led to an important change in the treatment of patients with symptomatic ischemic heart disease in recent years. There is controversy concerning the incidence and prognostic significance of postprocedural increases in creatine kinase. The aim of this study was to assess the incidence of these elevations and the related factors and to observe the prognosis of patients with and without creatin kinase elevations. METHODS: We reviewed 447 patients in whom an angioplasty was done in our department from January 1997 to June 1998, excluding 138 patients with myocardial infarction in the previous four days or unsuccessful angioplasty. Creatine kinase was measured in all patients at 0, 4, 8 and 24 hours after angioplasty. We analyzed the incidence of elevated levels of creatine kinase following coronary surgery and the characteristics of the patients in comparison with a control group made up of patients who, at a similar time had undergone a similar angioplasty procedure including, a similar vessel and type of lesion, and equivalent left ventricular function but without elevated serum levels of creatine kinase. Major adverse coronary events were defined as: cardiac death, nonfatal myocardial infarction, new revascularization and unstable angina in which hospitalization was required. RESULTS: Out of 309 patients studied, an elevation in creatine kinase was observed in 24 patients (7.7%). Complications related to the procedure were found in 50% of these elevations, most of which involved side branch occlusion. There were no differences with respect to the demographical or anatomical characteristics of the lesions in the groups studied. During the follow-up of 9.5 months, complications were observed in 37.5% of the group of patients with elevated creatine kinase levels and in 20% of the control group, but this difference did not achieve statistical significance. CONCLUSIONS: Creatine kinase elevations are produced in 7.7% of the patients after coronary angioplasty. Complications related to the procedure were observed in 50% of the cases, most being side branch occlusion and no complications were seen in the remaining patients. Continuous measurement of creatine kinase after angioplasty shows a low sensitivity for detecting complications during follow-up. New, more sensitive and specific cardiac markers, such as troponin, could define this group of patients.

Does angina the week before protect against first myocardial infarction in elderly patients?

Mortality rates for coronary artery disease are greater in elderly patients. Although prodromal angina occurring shortly before an acute myocardial infarction (MI) has protective effects against ischemia, this effect has not been well documented in older patients. This study investigated whether angina 1 week before a first MI provides protection in this group of patients. A total of 290 consecutive elderly (>64 years old, n = 143) and adult patients (<65 years old, n = 147) with a first MI were examined to assess the effect of preceding angina on the short- and long-term prognosis. Elderly patients with a history of prodromal angina were less likely than those without angina to experience in-hospital death, heart failure, or the combined end point of in-hospital death and heart failure (6% vs 20.4%, p = 0.02; 10% vs 23.7%, p = 0.07; 14% vs 32.3%, p = 0.01, respectively). Left ventricular function was more frequently depressed (ejection fraction <40%) in elderly patients without (44.8%) than with (26%, p = 0.04) preinfarction angina, and the incidence of arrhythmias (complete heart block and ventricular fibrillation) was greater in the former group (16.1% vs 4%, p = 0.03). Multivariate analysis confirmed that the presence of preinfarction angina was an independent predictor of in-hospital death and heart failure in older patients (odds ratio 0.28, p = 0.009). The occurrence of angina 1 week before a first MI may confer protection against in-hospital adverse outcomes, and may preserve left ventricular function in older patients.

[Quality control and improvement of the care provided to the patient with acute myocardial infarction. Implementation of a quality assurance program]. / Garantía y mejora de calidad de la atención al paciente con infarto agudo de miocardio. Implantación de un programa de calidad.

INTRODUCTION AND OBJECTIVES: Hospital care of patients with acute myocardial infarction involves a series of therapeutic measures and risk stratification which are a must since their efficacy has been clearly demonstrated. The aim of this study was to develop an internal program to guarantee and improve the quality of hospital care to acute myocardial infarction patients. METHODS: A medical audit was carried out for evaluation. Seven evaluation criteria considered as class I by the guidelines on the management of acute myocardial infarction patients were analyzed in the discharge report of 163 consecutive patients. Following analysis of the results corrective measures were implemented. In the second phase reevaluation of 40 patients was performed to determine the efficacy of the adopted measures. RESULTS: Following the first evaluation the use of AAS, IECAS and the beta-blockers was found to be correctly indicated in 95, 80 and 72% of the patients, respectively. A strategy of the adequate stratification of risk was carried out and ventricular function was evaluated in 93 and 96% of the cases. Correct hypolipemia treatment was indicated in 54% of the cases with an adequate diet being prescribed in 100%. Three months after the intervention, 40 new patients were evaluated with all the criteria analyzed being fulfilled in 100% of the cases. CONCLUSIONS: The use of evaluation techniques and improvement in the quality of health care provided to cases of acute myocardial infarction allows the determination of the care undertaken and its correction if necessary in order to follow the guidelines recommended for the care of these patients.

Measurement of fractional flow reserve to assess moderately severe coronary lesions: correlation with dobutamine stress echocardiography.

BACKGROUND: New techniques to evaluate coronary artery disease, such as calculation of myocardial fractional flow reserve (FFR) with a guidewire and pressure transducer, provide a functional assessment of coronary lesions. The present study was designed to determine the correlation between FFR and dobutamine stress echocardiography in patients with moderately severe coronary stenosis in order to judge the usefulness of FFR for commonly encountered clinical problems. METHODS AND RESULTS: We studied 21 patients with 23 moderately severe coronary artery stenoses on angiography. The FFR was calculated and dobutamine stress echocardiography was performed to detect ischemia. Of the 16 stenoses with a negative FFR (> or = 0.75), dobutamine echocardiography also was negative. In the seven stenoses with a positive FFR (< 0.75), dobutamine echocardiography was positive in three. The efficacy of FFR in detecting ischemia that was confirmed with stress echocardiography was sensitivity 100%, specificity 80%, positive and negative predictive value 42.8%, and 100%, respectively, with a global predictive value 82.6%. A moderate degree of correlation was found between the two diagnostic tests (kappa [kappa] = 0.51). CONCLUSIONS: FFR correlates moderately well with dobutamine stress echocardiography in the assessment of moderately severe lesions in patients for whom coronary arteriography is usually indicated. However, its high negative predictive value makes FFR a useful aid in reaching clinical decisions promptly in the hemodynamics laboratory.

Clinical management of patients with coronary syndromes and negative fractional flow reserve findings.

AIMS: New interventional techniques to diagnose coronary artery stenosis, such as calculation of myocardial fractional flow reserve (FFR) with a guidewire and pressure transducer, provide a functional assessment of coronary lesions. The present study was designed to investigate the occurrence of cardiac events in patients with coronary syndromes and negative FFR findings in moderately severe coronary stenosis in order to determine the usefulness of this technique in predicting coronary events during follow-up for problems commonly encountered in clinical practice. A further objective was to evaluate the safety of deferring angioplasty in patients with a negative FFR result. METHODS: We studied 43 patients with 44 moderately severe coronary artery stenoses on angiography and FFR > or = 0.75. Mean age of the patients was 58 +/- 11.4 years. The indications for coronary angiography included recent unstable angina in 24 (55.8%) patients, recent acute myocardial infarction in 10 (23.2%) patients, 5 (11.6%) patients with a coronary stent who had symptoms of uncertain cause, and stable angina in 4 (9.3%) patients. RESULTS: During a mean follow-up period of 10.7 +/- 5.9 months, clinical events (unstable angina) occurred in five patients. In three patients, the initially investigated artery was involved, and in the two patients who required coronary revascularization, unstable angina was related with an artery different from the one studied initially. CONCLUSIONS: Patients with recent coronary syndromes and negative FFR findings in moderately severe coronary stenosis were unlikely to have cardiac events during a 10-month follow-up period. Our findings suggest that FFR is a potentially useful indicator of the likelihood of cardiac events and thus represents a useful aid in clinical decision-making in the hemodynamics laboratory. This diagnostic technique also is potentially useful in identifying patients for whom angioplasty can be safely deferred.

[Actuarial follow-up after percutaneous mitral valvulotomy. Incidence and event-predicting factors]. / Seguimiento actuarial tras valvulotomía mitral percutánea. Incidencia y factores predictores de eventos.

INTRODUCTION: The goal of this study is to analyse the follow-up of patients who underwent percutaneous mitral valvuloplasty and the predicting factors of event-free survival. METHODS: We analysed 220 consecutive valvuloplasty performed between 1988 and 1996 in order to establish the incidence of events (death, restenosis, mitral valve surgery, New York Heart Association class IV, new valvuloplasty or systemic embolia) and the baseline and postprocedural characteristics predicting events, during a mean follow-up of 42 months (range 1-96 months). RESULTS: Overall survival was 94.7%, and event-free survival was 59.2% at 96 months. We analyzed the baseline characteristics in order to predict the mid-term outcome (actuarial survival Kaplan-Meier method) that atrial fibrillation (p < 0.01), age > or = 56 years (p < 0.005), and echocardiographic score > or = 9 (p < 0.005) were baseline characteristics related to adverse events in follow up. An index based on the number of adverse factors in the baseline characteristics provided a significant difference in concerning the number of follow up to even-free between the group without baseline adverse characteristics and the group with two (p = 0.008, OR = 4.5), or three adverse characteristics (p = 0.005, OR 6.4). Among the postprocedural characteristics, while patients with mitral valve area after valvuloplasty > or = 1.5 cm2 had an event-free survival of 72.9% at 96 months, those with postprocedural mitral valve area < 1.5 cm2 had an event-free survival of 10.5% (log-rank test p < 0.0001). CONCLUSIONS: Mid-term event-free survival after percutaneous mitral balloon valvuloplasty can be predicted by baseline and postprocedural characteristics. Age > or = 56, echocardiographic score > or = 9 and atrial fibrillation are baseline factors related with adverse events. Patients with 0 or 1 baseline adverse factors do not have significant differences concerning mid-term outcome while, those with 2, and above all, 3 adverse baseline characteristics have a poorer event-free survival. Mitral valve area > or = 1.5 cm2 is the only postprocedural independent predictor of event-free survival.

[Preoperative coronarography in heart valve disease patients. A probability analysis of coronary lesion]. / Coronariografía preoperatoria en pacientes valvulares. Análisis de probabilidad de lesión coronaria.

INTRODUCTION AND OBJECTIVES: The indication of preoperative coronary angiography is routinely performed for patients who are going to valve replacement surgery. The need of coronary angiography is based on age, gender and previous angina, but it is not usually based on risk factors. The purpose of this study has been to find markers to predict the probability of coronary lesion in this group of patients. PATIENTS AND METHODS: We studied retrospectively a population of 541 patients with valvular heart disease who underwent preoperative coronary angiography from 1989 to 1994. Mean age was 61.8 (range 34-82). There were 301 men and 240 women. We analyzed in each patient different variables such as age, gender, previous angina, hypertension, diabetes mellitus, tobacco and familial predisposition. We correlated these variables with the presence of coronary lesion by multivariate analysis. RESULTS: There were 73 patients with coronary lesion greater than 50%. The prevalence of significant coronary artery disease was 13.4%. Angina was present in 34.6%. The risk of coronary lesion was defined as odds ratio: previous angina 3.3; tobacco 2.6; diabetes 2.2; hypertension 1.8 and age 1.4. The others variables were not predictor of coronary lesion. The probability of coronary lesion in patients without those variables (angina, tobacco, diabetes, hypertension) was 4%. If we analyzed age, the probability of coronary lesion was 3% in patients under 65 years and 6% above 65 years. CONCLUSIONS: The lack of previous angina and at least the three risk factors described as predictors of coronary lesion (hypertension, tobacco and diabetes) can define a group of patients with a very low prevalence of coronary lesion, especially if they are under 65 years. It can allow us to avoid preoperatory coronary angiography in patients who undergo valve replacement.