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In 500 patients suffering from angina pectoris (454 males, 46 females) in whom coronary angiography had been performed a dipyridamole test was carried out. The test was positive in 319 of 396 patients with stenosing coronary heart disease (sensitivity 80%); ECG changes typical of ischaemia were demonstrated in 51%. The exercise ECG test was positive in only 68% of 229 patients with coronary heart disease. Among 104 patients without stenosing coronary heart disease the dipyridamole test was false-positive in 47, giving a specificity of 55%, while in 17 (16%) there were false-positive ECG-changes. The exercise test was falsely positive in 20 of 38 patients without stenosing coronary heart disease (specificity of 47%). Coronary blood flow was measured with the argon technique in 19 of 47 with a false-positive dipyridamole test and three with a false-positive exercise ECG. Maximal pharmacologically induced coronary blood flow was significantly reduced in all so that the diagnosis of "atypical coronary heart disease" or "small vessel disease" was made. The dipyridamole test or the exercise ECG test were falsely positive in these patients only with regard to the coronary arteriogram, correctly positive, however, in relation to angiographically non-demonstrable coronary blood flow abnormalities. The dipyridamole test is complementary to the exercise ECG test and has comparable accuracy. The same precautions must be observed for both tests.

Haemodynamic effects of 5-isosorbide mononitrate (5-ISMN) were studied at rest and on exercise in 31 patients with angiographically confirmed coronary heart disease. A decrease in arterial blood pressure and mean pulmonary artery pressure without significant change in heart rate, cardiac output and stroke volume occurred both at rest and on exercise after 20 mg of 5-ISMN to 12 patients. Administration of 50 mg 5-ISMN to 19 patients achieved greater decrease in mean pulmonary artery pressure; cardiac output and stroke volume were highly significantly reduced at rest, while on exercise both cardiac output and stroke volume remained unchanged. Ten patients, in whom after a single dose of 50 mg 5-ISMN the mean pulmonary artery pressure at rest and on exercise had decreased 28% and 45%, respectively, with a definite rise in exercise tolerance, repeat acute administration of a single dose of 50 kmg 5-ISMN produced a fall in mean pulmonary artery pressure at rest by 20% after 50 mg three times daily for four weeks. On exercise the fall was only 14% below the control levels before treatment. In addition, exercise tolerance was reduced. These results indicate that acute administration of 5-ISMN at rest and on exercise decreases cardiac work load. But on chronic administration of high doses, tolerance to the drug may develop.

The haemodynamic and antianginous efficacy of percutaneous nitroglycerin was evaluated in 24 patients with coronary heart disease. Groups of 8 patients each received one, two or four patches (nitroglycerin liberation 5 mg per patch within 24 hours). Prior to application and after 1 and 2 hours cardiac frequency, arterial and pulmonary arterial pressures and exercise tolerance were assessed. Cardiac frequency and arterial pressure showed no relevant changes after application of patches. The mean pulmonary arterial pressure decreased after application of one or two plasters by 18.5 and 22.2% at rest and by 12.7 and 21.1%, respectively, during exercise. The working capacity showed a trend towards improvement only. With four nitroglycerin patches the mean pulmonary arterial pressure at rest was lower by 26.2% and during exercise by 39.1%. The working capacity rose significantly by 48.7%. Comparison of these effects with oral single dosage of 20 mg 5-isosorbide mononitrate (ISMN) showed that two simultaneously administered plasters did not achieve efficacy of 20 mg 5-ISMN, four plasters, however, were more effective.

An automatic, implantable cardioverter-defibrillator (AICD) which generates a high-energy current impulse is now available for the management of treatment-resistant malignant ventricular arrhythmias. Such a device (manufactured by Intec/CPI) was implanted into eight patients with coronary heart disease or dilated cardiomyopathy, and in four after surgery for postinfarction ventricular arrhythmias. All patients had had life-threatening episodes of ventricular fibrillation or tachycardia: the arrhythmias were refractory to multiple drug therapy (mean of 6.8 antiarrhythmia drugs per patient). The threshold energy for converting ventricular fibrillation was 9.6 Joules +/- 5.7. Except for one bacterial infection of the electrodes, there were no serious complications. During a mean observation period of 13.6 months 21 electrophysiologically induced and 105 spontaneous tachyarrhythmias were successfully terminated by the AICD. No malfunctions occurred and there was no death due to an arrhythmia.

In a prospective study of 23 patients the clinical effects of rate-adapted activity-sensed (by mechanical resonance oscillations) pacing (Activitrax system) were tested over a mean period of 8.1 +/- 3.8 months. This form of pacemaker treatment was used when, after exercise and on long-term ECG monitoring, the spontaneous heart rate had not exceeded 85 beats per min and there had been symptoms of decreased exercise tolerance. Lasting improvement in physical exercise tolerance was achieved in 11 of 17 patients after changing from fixed-rate to rate-adapted pacing. Treadmill ergometry, randomised in the fixed-rate or rate-adapted mode, brought about a significant rise in exercise tolerance (P greater than 0.01). Contrary to results after external influences, insufficient rate increases in five patients in the course of static stress was of clinical significance and thus narrow the indications for this type of pacing.

It is important that the medical profession plays a significant role in critically evaluating the use of diagnostic procedures and therapies as they are introduced and tested in the detection, management, or prevention of disease states. Rigorous and expert analysis of the available data documenting

Alonso-Garcia, Carina Blomstrom-Lundqvist, Guy de Backer, Marcus Flather, Jaromir Hradec, Committee for Practice Guidelines & Policy Conferences Members, Werner W. Klein, Angeles Gregoratos, Loren F. Hiratzka, Alice K. Jacobs, Richard O. Russell, Sidney C. Smith, Jr., ESC J. Gibbons, Elliott M. Antman, Joseph S. Alpert, David P. Faxon, Valentin Fuster, Gabriel Levy, Robert L. McNamara, Eric N. Prystowsky, L. Samuel Wann, D. George Wyse, Raymond Harry J. Crijns, Robert L. Frye, Jonathan L. Halperin, G. Neal Kay, Werner W. Klein, Samuel Committee Members, Valentin Fuster, Lars E. Ryden, Richard W. Asinger, David S. Cannom, Collaboration With the North American Society of Pacing and Electrophysiology Guidelines for the Management of Patients With Atrial Fibrillation) Developed in Committee for Practice Guidelines and Policy Conferences (Committee to Develop Association Task Force on Practice Guidelines and the European Society of Cardiology Executive Summary A Report of the American College of Cardiology/American Heart ACC/AHA/ESC Guidelines for the Management of Patients With Atrial Fibrillation

Under the heading ‘Hypertension, diabetes, and other disorders’ on page 1358, the guidelines1 lean on the taskforce report on CVD prevention2 suggesting ‘considering a lower threshold for institution of pharmacological therapy for hypertension (130/85) for patients with established coronary heart disease (which would include patients with …

The accuracy of ST-segment analysis by means of the Marquette-Laser-Holter system was compared with conventional ECG registration during ergometry. In 26 patients with angiographically confirmed coronary heart disease conventional chest leads and long-term ECGs were recorded simultaneously during standardized exercise. Simultaneously registered ST-segments in V5 and Holter CM5 were compared, with the results correlating well (r = 0.91) for any recorded abnormal repolarizations.

Guidelines and Expert Consensus Documents aim to present management recommendations based on all of the relevant evidence on a particular subject in order to help physicians select the best possible management strategies for the individual patient suffering from a specific condition, taking into account the impact on outcome and also the risk–benefit ratio of a particular diagnostic or therapeutic procedure. Numerous studies have demonstrated that patient outcomes improve when guideline recommendations, based on the rigorous assessment of evidence-based research, are applied in clinical practice. A great number of Guidelines and Expert Consensus Documents have been issued in recent years by the European Society of Cardiology (ESC) and also by other organizations or related societies. The profusion of documents can put at stake the authority and credibility of guidelines, particularly if discrepancies appear between different documents on the same issue, as this can lead to confusion in the minds of physicians. In order to avoid these pitfalls, the ESC and other organizations have issued recommendations for formulating and issuing Guidelines and Expert Consensus Documents. The ESC recommendations for guidelines production can be found on the ESC website.1 It is beyond the scope of this preamble to recall all but the basic rules. In brief, the ESC appoints experts in the field to carry out a comprehensive review of the literature, with a view to making a critical evaluation of the use of diagnostic and therapeutic procedures and assessing the risk–benefit ratio of the therapies recommended for management and/or prevention of a given condition. Estimates of expected health outcomes are included, where data exist. The strength of evidence for or against particular procedures or treatments is weighed according to predefined scales for grading recommendations and levels of evidence, as outlined in what follows. The Task Force members of the writing panels, …

Sidney C. Smith, Jr, MD, FACC, FAHA, FESC, Chair; Alice K. Jacobs, MD, FACC, FAHA, Vice-Chair; Cynthia D. Adams, MSN, APRN-BC, FAHA; Jeffery L. Anderson, MD, FACC, FAHA; Elliott M. Antman, MD, FACC, FAHA[‡][1]; Jonathan L. Halperin, MD, FACC, FAHA; Sharon Ann Hunt, MD, FACC, FAHA; Rick Nishimura

Seventy-nine patients with angiographically documented coronary artery disease were studied with exercise ECG and Holter ECG for ischaemic ST segment changes. Fifty-four patients (68.3%) had ischaemia on exercise, 48 patients (62.0%) had ischaemic ST segment depression during Holter monitoring. Twenty-four (30%) of the patients with a positive exercise test and 30 (61%) with a positive Holter ECG were asymptomatic during the test, 83.7% of the total count of 456 episodes of spontaneous ischemia during Holter monitoring were silent. Forty-four patients (55.7%) had ischaemic ECG changes during exercise and Holter ECG, 20 patients (25.3%) were negative on both tests. Ten (12.7%) had only a positive exercise test and five (6.3%) only a positive Holter ECG. The sensitivity of Holter monitoring for the detection of ischaemia in patients with coronary artery disease is comparable to the sensitivity of the exercise ECG.

The analysis of ST segment changes during Holter monitoring is one important diagnostic method for detection and diagnosis of silent myocardial ischaemia. To assess the specificity and sensitivity of ST segment alterations as a diagnostic tool, 106 healthy medical students (43 females, 57 males, aged 18-36 years, mean age 26 +/- 4 years) and 26 children (14 females, 12 males, aged 12-17 years, mean 14 +/- 3 years) with no history of heart disease and normal findings during physical examination were studied by exercise stress test and Holter monitoring. Criteria for exclusion were a history of hypertension, diabetes mellitus and ST segment alterations during conventional 12-lead ECG. Due to these criteria, eight volunteers had to be excluded from the study. The exercise stress test (maximum work load protocol) revealed no pathological ST segment depressions. During Holter monitoring seven episodes of ST segment depressions (greater than or equal to 1.0 mm planar or downsloping, duration greater than or equal to 1.0 min) were found. Typical ST segment depressions detected by Holter monitoring may be found in healthy subjects. Therefore this finding has to be considered cautiously as a diagnostic tool for evaluation of patients with suspected coronary heart disease.

On the occasion of a routine medical check-up 256 out of 1100 individuals with an accumulation of coronary risk factors were screened for silent myocardial ischaemia by exercise testing and Holter monitoring. Of these individuals 5.5% had a pathological exercise test, 7.4% had ischaemia-like events on the Holter ECG, 11.3% had at least one pathological test, but only 1.6% had ischaemic signs in both ECG tests. The outcome of the ECG tests appears to be independent of the type and the total number of risk factors. To date, 13 of the 29 individuals with a positive test have undergone thallium myocardial imaging: only three individuals had signs of ischaemia. Holter monitoring and exercise ECG show comparable results in this population. The pathological ECG findings were only partly confirmed by the thallium test. The follow-up will show the prognostic significance of the ECG changes.

Following the administration of isosorbide dinitrate (ISDN) to patients with coronary heart disease, pulmonary artery pressure, left-ventricular filling pressure, and myocardial oxygen consumption decline. As a result, patients experience a reduction in the frequency and severity of anginal attacks and their exercise tolerance increases. These acute effects of single doses of ISDN have been confirmed in numerous studies (2–4, 12, 13, 18, 23, 25–28).

The transdermal administration of glyceryl trinitrate or isosorbide dinitrate has been demonstrated to be effective in patients with coronary heart disease or chronic heart failure [2, 4, 7–9, 20–26]. This route of administration bypasses the liver and thus the “first-pass” effect of passage through the liver [19]. Transdermal administration of glyceryl trinitrate is thus similar to i. v. administration [2, 3].

In a series of 44 patients, 5 females and 39 males, the incidence and dynamic behavior of ventricular late potentials was studied. Using a home-built high resolution electrocardiogram equipment ventricular late potentials were found within the ST segment in 27/44 patients, and in 11 patients were the late potentials observed intermittently. In 21/44 patients late potentials were also present after the T wave, in 5 individuals intermittently.

Sudden cardiac death is one of the unsolved problems in clinical cardiology. This syndrome has been reported to be associated in most cases (more than 80%) with underlying coronary heart disease, and in the remaining cases with cardiomyopathies, aortic stenosis, mitral valve prolapse, QT syndrome and WPW syndrome. From the experiences in the literature patients with severe coronary heart disease and with poor left ventricular function and complex ventricular arrhythmias carry a particularly high risk of sudden cardiac death. In addition, from recent studies the detection of (abnormal) ventricular late potentials within the ST segment of the high gain amplified, signal averaged surface ECG seems to provide a new marker of increased left ventricular irritability in CHD patients. One of the most important diagnostic goals in sudden death candidates is the assessment of ventricular vulnerability. This may be achieved by recording of complex ventricular arrhythmias, by detection of ventricular diastolic potentials within the ST segment, and by provocation of repetitive ventricular response with programmed ventricular stimulation. The identification and characterization of the risk of successfully resuscitated pre-hospital cardiac arrest victims to develop a new fatal event constitutes a major clinical problem. Based on the experiences from the literature and our own studies a high risk profile of those SD candidates to develop a new fatal event may be outlined as follows: Bradycardia ofless than 60 bpm after successful resuscitation, atrio- or intraventricular block, severe coronary heart disease with triple vessel disease, low left ventricular ejection fraction and severe contraction abnormalities, complex ventricular arrhythmias, presence of ventricular late potentials, and inducibility of repetitive ventricular response.

In a total of 40 patients, 10 females and 30 males, aged 42 to 65 years (mean: 53 ± 6 years) the diagnostic accuracy of three methods that might indicate left ventricular vulnerability, has been tested. These methods comprise the spontaneous occurrence of complex ventricular arrhythmias (Lown’s classes IVa and b and ventricular tachycardias), the recovery of ventricular late potentials within the signal averaged surface ECG, and the induction of repetitive ventricular response during programmed right ventricular stimulation. The “gold standard” was the out-of-hospital documented spontaneous occurrence of ventricular tachycardias and/or fibrillation in each of these 40 patients, 21 of whom had to be resuscitated by DC shock.

In patients with chronic recurrent attacks of supraventricular, and in rare cases of ventricular tachycardia, chronic antitachycardia pacing using implantable pacemakers with different termination modes may be an attractive alternative to chronic drug therapy, particularly in patients with drug refractoriness or serious side effects. Before implantation of an antitachycardia pacemaker various clinical and technical conditions have to be considered and tested, such as reproducibility of tachycardia termination, effective and safe termination mode, optimal lead position, conditioning of the tachycardia by antiarrhythmic drugs for safe electrical termination, and the possible deterioration of the tachycardia by the antitachycardia pacing mode itself.

Long-term treatment of patients with recurrent attacks of ventricular tachycardia (VT) and an increased risk of sudden death may be crucial, since in some patients antiarrhythmic drugs may be ineffective or may induce serious side effects. Thus, endo-epicardial cardioversion-defibrillation seems an attractive alternative for short-term, and probably also long-term treatment of recurrent VT and ventricular fibrillation (VF).

Since it’s introduction into clinical cardiology PTCA proved to be an effective method for reduction of coronary stenoses, thus leading to relief of angina pectoris and an increase of exercise tolerance in CHD patients. The success rates of PTCA depend on the type of lesion, catheter material, experience of the angiographer, and on the inflation pressure and inflation time used. With longer inflation times possible hazards of PTCA-induced ischemia may arise like LV pump failure or the occurrence of dangerous ventricular arrhythmias. Myocardial protection during PTCA may be achieved by means of intracoronary (ic.) administration of Nitro glycerine and/or Nifedipine (or other calciumantagonists as well) prior to inflation, or by simultaneous perfusion of the dependent myocardial area with arterial blood during the whole inflation period. Several studies using ic.-Nitroglycerine and/or Nifedipine have shown that sometimes symptoms and particularly signs of myocardial ischemia on PTCA may be delayed by these drugs and the occurence of ventricular arrhythmias decreased, thus allowing potentially longer inflation periods. On the other hand, using quantitative LV angiography we could demonstrate that the impairment of global and regional LV contraction due to PTCA-induced ischemia was considerably and significantly less pronounced when using simultaneous perfusion with arterial blood during inflation. Administration of Nitroglycerine and/or Nifedipine by ic.-route seems to be a simple, rapid and safe method of myocardial protection from PTCA-related ischemia, but it may not preserve LV global and regional performance to such a degree as could be achieved using perfusion with arterial blood. The perfusion method may, therefore, provide the opportunity to also attempt PTCA in patients with multiple vessel disease and severely impaired left ventricular perfomance, as well as in individuals with left main stenoses.

In 70 patients (3 females and 67 males), aged 16-72 years (mean: 51 +/- 9 years), the low noise ECG was recorded from body surface by the signal averaging and the high resolution beat-to-beat techniques. We found 61 patients were suffering from coronary heart disease, 4 had atypical coronary heart disease (syndrome X), 4 had dilatative cardiomyopathy, and one had the long QT syndrome (Romano-Ward syndrome). We found the following recovery rates for ventricular late potentials within the ST segment with the averaging technique: clearcut in 13/53 patients, doubtful in 16/53 patients, and late potentials absent in 26/53 patients. With the beat-to-beat technique the following recovery rates were found: clearcut late potentials in 27/70 patients, doubtful in 23/70 patients, none in 20/70 patients, and intermittently occurring late potentials in 18/70 patients (categorized as doubtful late potentials). When comparing the detection of late potentials with both methods in individual patients, we found concordant results in 39/53 patients studied (positive with both methods in 24/53 patients, negative with both methods in 15/53 patients), and discordant results in 14/53 patients (positive with the beat-to-beat technique and negative with the averaging technique in 12 individuals, negative with the beat-to-beat technique and positive with the averaging technique in the remaining 2 patients). The correlation between the incidence of late potentials and the presence of exercise-induced myocardial ischemia (submaximal bicycle exercise) was higher when using the high resolution beat-to-beat technique, as holds also true for the correlation to complex ventricular arrhythmias.(ABSTRACT TRUNCATED AT 250 WORDS)

Several investigators have judged the burst overdrive pacing mode to be effective in tachycardia termination during right ventricular programmed stimulation. The aim of the study was to investigate the long-term results of burst overdrive pacing by means of an implanted, programmable burst pacemaker (Intermedics Cybertach 60) in the treatment of drug-refractory supraventricular (n = 3) and ventricular (n = 3) tachycardias. Therefore 6 patients were repeatedly controlled during a follow-up period of up to 3 years. In 4/6 patients the parameters of the burst stimulation had to be changed within the first 6 months after the implantation. All 6 patients needed an additional antiarrhythmic drug treatment for the tachycardia conditioning. Due to a significant reduction of the tachycardias and hospitalisations all patients could normalize their lives. In a 20 year old man the battieries ran out after a 2 year period of excellent antitachycardia function. The patient was hospitalised due to continuous burst pacing, even during sinus rhythm or premature ventricular beats.

In all, 47 patients aged 28–63 years (mean age 50.4 ± 7.0 years) who had angiographically confirmed coronary disease were investigated. The purpose of the study had been explained to all the patients and they had given consent in writing. All drugs acting on the coronary system were withdrawn 72 h before the investigation. Short-acting nitrates for aborting attacks were permitted up to 6 h before the investigation. Patients with heart defects, arrhythmias, marked arterial hypertension, lung diseases, severe angina pectoris symptoms, and radiological or clinical evidence of heart failure were not admitted to the investigation. All investigations were carried out in the early morning to avoid diurnal variations [19].