The importance of ambulatory ECG monitoring for determining the prognosis of patients with stable stenocardia]

149 patients with coronary artery disease and stable angina pectoris underwent coronary angiography and had coronary artery stenosis over 50 per cent. All the patients were also subjected to 24-h Holter monitoring at primary examination and 12-18 months after it. Typical ischemic ST changes were defined by transient horizontal or descending ST depressions > 1.0 mV (measured 80 ms after the J point) lasting at least for a minute. 75 (50.3 per cent) patients had episodes of silent myocardial ischemia. The course of the disease was assessed in follow-up period of 12-18 months. Four variants of the course were determined: cardiac events (16 patients), the disease progression (33 patients), a stable course (75 patients), clinical remission (25 patients). A significant correlation between the occurrence, the slope and duration of silent ischemia, the data of selective coronary angiography and clinical course of ischemic heart disease was established. Cardiac events occurred in 87.5% of the patients with silent myocardial ischemia who had total ischemic burden 30 minutes or more and/or ST-segments decrease 3.0 mm and more during heart rate less than 100 beat-min. The stable course was registered in patients with silent ischemia or without it with similar frequency. Clinical remission of angina pectoris in the patients with silent ischemia was observed rarely. The results of this study demonstrate that silent ischemia is an important prognostic factor.     

Prognostic value of training-induced change in peak exercise capacity in patients with myocardial infarcts and patients with coronary bypass surgery

An inverse association between mortality and exercise capacity has been demonstrated previously in patients with coronary artery disease. Physical training generally increases exercise capacity. Only 1 study investigated the prognostic value of exercise capacity after training, but only in a limited number of patients. No data are available on the relation between mortality and the change in exercise performance with training. Peak oxygen uptake (VO2) was measured before and after a 3-month, predominantly dynamic training period in 417 patients with coronary artery disease. Apart from peak VO2, several patient characteristics, risk factors for cardiovascular disease, and exercise data were considered in a Cox proportional-hazards model. Peak VO2 had increased by 33% after the training period. During the total follow-up of 2,583 patient-years, 37 patients died. The cause of death was cardiovascular in 21. The prognostic value of peak VO2 was higher after training than before training, even after adjustment for age and other significant covariates. Cardiovascular mortality decreased more with greater increases in peak VO2 after training. The relative hazard rate of 0.98 indicates that a 1% greater increase in peak VO2 after training would be associated with a decrease in cardiovascular mortality of 2%. No differences in prognostic value and in training effects were observed between patients with myocardial infarcts and patients after coronary bypass grafting. Peak VO2, evaluated after a physical training program, and its change in response to training are independent predictors for cardiovascular mortality in patients with coronary artery disease.     

Circadian variation of ventricular arrhythmia recurrences after cardioverter-defibrillator implantation in patients with healed myocardial infarcts

Past studies using Holter monitoring and retrospective reviews of death certificates have documented peak occurrence of sudden death and nonsustained ventricular tachycardia (VT) in the morning hours. We used the Ventritex Cadence device (Ventritex, Sunnyvale, California) which documents the date and time of all stored arrhythmias leading to device therapy to evaluate the circadian pattern of sustained ventricular arrhythmia recurrence. Mean follow-up after defibrillator implantation was 628 +/- 285 days. All 390 patients had at least 1 episode (range 1 to 43) of sustained VT documented from analysis of the stored electrograms associated with an arrhythmia event. Stored electrograms were available for review and analysis in 3,041 device detections; 349 stored events were excluded because they did not fulfill the diagnostic criteria for VT or failed to document the onset of the ventricular arrhythmia at the beginning of the recorded event of the arrhythmia episode. Criteria for the diagnosis of VT or ventricular fibrillation were met in 2,692 arrhythmia episodes occurring in 390 patients. There was circadian variation for ventricular arrhythmia recurrence for the whole patient group with the data fit to the sinusoidal density function: f(t) = 126 - 51 x cos (-57 + 2 pi t/24) - 25 x sin (63 + 2 pi t/12) (p < 0.0001). Ventricular arrhythmia occurrence rate was lowest between 2:00 and 3:00 A.M., and highest between 10:00 and 11:00 A.M. In addition, the same circadian pattern was demonstrated regardless of patient age, gender, left ventricular ejection fraction (< 35% or > or = 35%), and VT cycle length (< 300 or > or = 300 ms).(ABSTRACT TRUNCATED AT 250 WORDS)     

Coronary stenosis progression differs in patients with stable angina pectoris with and without a previous history of unstable angina

OBJECTIVES: To compare the evolution of stenoses responsible for acute coronary events with those not associated with acute coronary syndromes. METHODS AND RESULTS: We prospectively studied angiographic stenosis progression in 190 stable angina patients, with single vessel disease, who were awaiting non-urgent coronary angioplasty. Sixty four patients had a previous history of unstable angina (Group 1) and 126 patients had no history of unstable angina (Group 2). Culprit stenoses were classified as "complex' or "smooth'. At restudy, 8 +/- 4 months after the first angiogram, 12 of 63 culprit stenoses in Group 1 had progressed and seven of 125 in Group 2 (19% vs 6%, P = 0.0044). Thirteen of 68 complex culprit stenoses had progressed, compared with only 6 of 120 smooth culprit stenoses (19% vs 5%, P = 0.003). Coronary events occurred in 12 Group 1 patients and nine Group 2 patients (P = 0.02). CONCLUSIONS: In patients with stable angina, stenoses associated with previous episodes of unstable angina are more likely to progress than stenoses not associated with previous unstable angina. Unstable coronary atherosclerotic plaques, even those that have been clinically stable for more than 3 months, may retain the potential for rapid progression to total occlusion.     

Lung-heart ratio in stress thallium myocardial perfusion imaging in patients with a history of a previous pneumonectomy

Increased TI-201 lung-heart ratio after treadmill exercise or pharmacologic stress is an indicator of left ventricular dysfunction. After pneumonectomy, it is not reliable because of increased pulmonary circulation in the remaining lung. The authors present an example of normal stress TI-201 myocardial perfusion imaging with an increased lung-heart ratio of TI-201 uptake.     

Effect of a standardized meal on the threshold of exercise-induced myocardial ischemia in patients with stable angina

OBJECTIVES: This study was undertaken to determine the effect of a standardized meal on the ischemic threshold and exercise capacity in a series of 20 patients with stable angina, exercise-induced ischemia and reversible exercise-induced perfusion defects. BACKGROUND: It is generally accepted that exercise tolerance in patients with angina is reduced after a meal. However, studies that have addressed this phenomenon have yielded results that are contradictory and inconclusive. METHODS: Two exercise tests using the Bruce protocol with technetium-99m (99mTc)-sestamibi were performed on consecutive days in a randomized order. One test was performed in the fasting state and the other 30 min after a 1,000-calorie meal. RESULTS: In the postprandial state, exercise time to ischemia was reduced by 20% from 248 +/- 93 s to 197 +/- 87 s (p = 0.0007), time to angina by 15% from 340 +/- 82 s to 287 +/- 94 s (p = 0.002) and exercise tolerance by 9% from 376 +/- 65 s to 344 +/- 86 s (p = 0.002). Rate-pressure products at these exercise test end points were not significantly different in the fasting and postprandial tests, and the quantitative 99mTc-sestamibi ischemia score was unchanged. CONCLUSIONS: In patients with stable angina, a 1,000-calorie meal significantly reduced time to ischemia, time to angina and exercise tolerance because of a more rapid increase in myocardial oxygen demand with exercise. The extent and severity of exercise-induced ischemia were unchanged.     

The effect of diltiazem on neurohumoral regulatory mechanisms in stenocardia patients

Effects were studied of diltiazem on parameters characterizing cardiohemodynamics, peripheral bloodflow, condition of atrial natriuretic peptide (ANUP), of cyclic nucleotides (cGMP), the renin-angiotensin system in patients with various manifestations of stenocardia. An inhibitory action of diltiazem on ANUP and cGMP secretion in a VEM-test was recordable but changes were not significant at the height of the drug action in rest. Improvement in myocardial contractility after the course treatment with the drug was accompanied by reduction in blood plasma levels of ANUP and cGMP. It is suggested that changes in ANUP concentration might be traced to improvement in the anginal course and to the drug effects such as lowering of myocardial oxygen demand, of pre- and afterload, improvement in the indices for myocardial contractility.     

Correlation of thallium uptake with left ventricular wall thickness by cine magnetic resonance imaging in patients with acute and healed myocardial infarcts

Myocardial infarction (MI) is characterized by cellular necrosis which undergoes fibrotic transformation over time. Cine magnetic resonance imaging (MRI) offers high-resolution 3-dimensional images of the left ventricular myocardium, allowing sampling of the myocardial wall thickness over the entire left ventricle. Tomographic (single-photon emission computed tomography [SPECT]) thallium images also provide 3-dimensional information on the location and level of thallium uptake, which has been shown to correlate with myocardial viability. The purposes of this study were: (1) to examine the relation between both end-diastolic and end-systolic wall thickness and normalized thallium-201 uptake over the left ventricle in a group of patients with MI, (2) to examine the relation between regional wall thickening and normalized thallium uptake, and (3) to examine the relation between thallium uptake and wall thickness both early and late after infarction. Twenty-four patients with MI underwent stress, redistribution, and reinjection thallium SPECT imaging and cine MRI within several days. Seventeen patients underwent imaging late after infarction and 7 underwent imaging early after infarction. Normalized thallium activity was correlated with MRI wall thicknesses at both end-diastole and end-systole for 18 segments for each ventricle. In addition, end-diastolic and end-systolic wall thicknesses were grouped by their corresponding thallium activity levels into percentiles. End-systolic wall thickness correlated significantly with normalized thallium uptake in 14 of 18 segments, end-diastolic wall thickness in only 4 of 18 segments, and wall thickening in only 3 of 18 segments. Mean values for end-diastolic and end-systolic wall thicknesses corresponding to severely reduced (<50%) normalized thallium activity were 9.9 +/- 1.1 and 8.5 +/- 0.6, respectively. Using receiver-operating curve analysis, end-systolic wall performed as a better diagnostic parameter than end-diastolic wall for identifying severely reduced thallium activity levels. For all levels of thallium activity, end-diastolic wall thicknesses were all thinner late versus early after MI, whereas end-systolic wall thickness was thinner only in the segments corresponding to severely reduced thallium activity. Based on these results, end-systolic wall thickness is the best noninvasive anatomic parameter of myocardial scar.     

Acute heavy alcohol intake increases silent myocardial ischaemia in patients with stable angina pectoris

PURPOSE: The purpose was to determine tumor neovascularisation via colour-coded Doppler (duplex) sonography and the "power mode", both visually and quantitatively, by means of videodensitometry. MATERIAL AND METHODS: 6 VX2 tumours of 4 to 11 mm size were implanted in 4 rabbits at various sites. The colour-coded duplex sonography and the new sonographic power technique were tested before and after having injected a new contrast medium (SH U 616A). RESULTS: If no contrast medium was injected, tumour neovascularisation was identified in only 50% of the cases. Injection of contrast medium increased signal intensity three to fourfold with all examined tumors. Combined use of the sonographic method by the power technique with injection of contrast medium is outstandingly suitable for tumor vessel imaging even of small tumors, as these initial results seem to show. CONCLUSION: If these results are corroborated by further studies, contrast-medium supported sonographic technique may possibly become established as an alternative method to other imaging procedures.     

MRI assessment of cerebral blood volume in patients with brain infarcts

MRI perfusion studies have focussed mainly on acute ischaemia and characterisation in ischaemia. Our purpose was to analyse regional brain haemodynamic information in acute, subacute, and chronic ischaemia. We performed 16 examinations of 11 patients on a 1.5 T MR images. Conventional and dynamic contrast-enhanced imaging were employed in all examinations. For the dynamic susceptibility sequences, a bolus (0.2 mmol/kg) of gadopentetate dimeglumine was injected. Reconstructed regional relative cerebral blood volume (rCBV) maps, bolus maps, and conventional images were analysed by consensus reading. In all examinations decreases in rCBV were observed in the lesions. The distribution of regional rCBV in lesions was heterogeneous. The rCBV of the periphery of the lesions was higher than that at their center. There was a correlation between the time since onset and abnormalities on the rCBV map and T2-weighted images (T2WI). In the early stage of acute stroke, the abnormalities tended to be larger on the rCBV than on T2WI. Many patterns of bolus passage were observed in ischaemic regions. rCBV maps provide additional haemodynamic information in patients with brain infarcts.     

False-positive cytological diagnosis of lung carcinoma in patients with pulmonary infarcts

Cytological examination of specimens obtained from the tracheobronchial tree has become an integral part of the evaluation of pulmonary lesions. Cytological criteria for the diagnosis of carcinoma exist and are well defined. Certain benign processes, however, may possess features strongly suggestive of carcinoma of the lung. We report 3 patients in whom a positive cytological diagnosis of carcinoma of the lung was made by an experienced cytopathologist. At operation each patient was found to have pulmonary infarct and no evidence of carcinoma. Review of this experience has disclosed cytological and clinical features that should alert the clinician to the possibility that the cytological diagnosis of lung cancer may be misleading in certain nonmalignant diseases.     

Beneficial effects of atrial natriuretic peptide on exercise-induced myocardial ischemia in patients with stable effort angina pectoris

BACKGROUND: It has been shown that atrial natriuretic peptide (ANP), an endogenous vasodilator, dilates coronary arteries and decreases coronary vascular resistance. The purpose of this study was to determine whether an intravenous administration of ANP attenuated exercise-induced myocardial ischemia in 14 patients with stable effort angina pectoris. METHODS AND RESULTS: The first 12 patients (patients 1-12) who had exercise-induced ST segment depression underwent treadmill exercise testing and the last seven patients (patients 8-14) underwent the exercise 201Tl-single-photon emission computed tomography (SPECT) study while synthetic 28-amino acid alpha-human ANP (0.1 micrograms/kg per minute) or saline was intravenously infused in a double-blind, cross-over manner. The duration of exercise testing was the same during ANP and saline infusion, which was determined in preliminary exercise testings in each patient to cause a transient perfusion defect and/or ischemic ST segment depression. During saline infusion, all 12 patients developed exercise-induced ischemic ST segment depression, whereas no significant ST segment depression appeared during ANP infusion. Average ST segment depression during ANP infusion was significantly less (p < 0.01) than that during saline infusion (0.0 +/- 0.0 versus 0.2 +/- 0.1 mV, mean +/- SD). The averaged extent and severity scores assessed by 201Tl-SPECT were smaller (p < 0.05) during ANP infusion than during saline infusion (extent score: 0.22 +/- 0.20 versus 0.42 +/- 0.20; severity score: 18.77 +/- 23.45 versus 38.24 +/- 24.04, respectively). ANP decreased resting systolic blood pressure from 125 +/- 15 to 110 +/- 15 mm Hg (p < 0.01) but did not alter resting heart rate. At peak exercise, systolic blood pressure, heart rate, and the rate-pressure products did not differ during ANP and saline infusion. At peak exercise, plasma ANP increased from 98 +/- 45 to 4,383 +/- 2,782 pg/ml and cGMP increased from 3.6 +/- 1.7 to 34.5 +/- 16.1 pmol/ml during ANP infusion; values were significantly higher than those during saline infusion (from 96 +/- 42 to 133 +/- 66 pg/ml and from 3.4 +/- 1.8 to 4.6 +/- 1.8 pmol/ml, respectively). CONCLUSIONS: An intravenous administration of ANP attenuated exercise-induced myocardial ischemia in patients with stable effort angina pectoris. Although the mechanism by which ANP attenuated myocardial ischemia was not defined, increased myocardial perfusion to the ischemic region might be an important factor.     

Effect of gallopamil on myocardial microperfusion in patients with stable effort angina: a randomized, cross-over, double-blind, placebo-controlled trial

We evaluated the efficacy and safety of daily administration of gallopamil 150 mg/day and its effects on myocardial perfusion in a medium-term, randomized, double-blind, cross-over, placebo-controlled trial. We studied 19 patients (17 males and 2 females; mean age 57 +/- 6.8 years) with stable effort angina, angiographically documented coronary artery disease and reversible perfusion defects during exercise thallium-201 myocardial scintigraphy of at least one segment of the left ventricle. After 2 weeks of a single-blind placebo run-in period, during which each patient underwent at least 2 exercise tests and a 48-hour Holter ECG recording, all patients were treated with either placebo or gallopamil 50 mg t.i.d. for 28 days. At the end of this period, patients crossed over to the alternate regimen. This phase was double blind. After treatment with placebo or gallopamil, patients underwent exercise tests, 24-hour Holter ECG recording and thallium-201 myocardial scintigraphy. Weekly angina frequency and trinitroglycerin (TNT) consumption and safety were also evaluated. No patients dropped out of the study because of major side effects. The number of total ischemic and symptomatic events recorded at 24-hour ECG monitoring, weekly angina frequency and TNT consumption were significantly reduced during gallopamil treatment. After gallopamil administration, exercise duration significantly increased (run-in: 419 +/- 116 s, placebo: 420 +/- 118 s, gallopamil: 511 +/- 144 s; p < 0.05), and ST segment depression was significantly reduced (run-in: -1.3 +/- 0.3 mm, placebo: -1.3 +/- 0.3 mm, gallopamil: -0.94 +/- 0.68 mm; p < 0.01), while heart rate, systolic blood pressure and rate-pressure product were unchanged at rest, at submaximal and at peak exercise. Qualitative and quantitative evaluation of myocardial perfusion and the myocardial uptake percentage of thallium-201 in ischemic zones were significantly improved by gallopamil treatment. These findings demonstrate that gallopamil can improve myocardial perfusion and reduce myocardial oxygen consumption.