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BackgroundIn contrast with the setting of acute myocardial infarction, there are limited data regarding the impact of diabetes mellitus on clinical outcomes in contemporary cohorts of patients with chronic coronary syndromes. We aimed to investigate the prevalence and prognostic impact of diabetes according to geographical regions and ethnicity.Methods and resultsCLARIFY is an observational registry of patients with chronic coronary syndromes, enrolled across 45 countries in Europe, Asia, America, Middle East, Australia, and Africa in 2009–2010, and followed up yearly for 5 years. Chronic coronary syndromes were defined by ≥1 of the following criteria: prior myocardial infarction, evidence of coronary stenosis >50%, proven symptomatic myocardial ischaemia, or prior revascularization procedure.Among 32 694 patients, 9502 (29%) had diabetes, with a regional prevalence ranging from below 20% in Northern Europe to ∼60% in the Gulf countries. In a multivariable-adjusted Cox proportional hazards model, diabetes was associated with increased risks for the primary outcome (cardiovascular death, myocardial infarction, or stroke) with an adjusted hazard ratio of 1.28 (95% confidence interval 1.18, 1.39) and for all secondary outcomes (all-cause and cardiovascular mortality, myocardial infarction, stroke, heart failure, and coronary revascularization). Differences on outcomes according to geography and ethnicity were modest.ConclusionIn patients with chronic coronary syndromes, diabetes is independently associated with mortality and cardiovascular events, including heart failure, which is not accounted by demographics, prior medical history, left ventricular ejection fraction, or use of secondary prevention medication. This is observed across multiple geographic regions and ethnicities, despite marked disparities in the prevalence of diabetes.ClinicalTrials identifierISRCTN43070564

The value of long-term electrocardiographic (ECG) monitoring was assessed in 14 patients (8 males, 6 females; mean age 21 [17-30] years) with the idiopathic long QT syndrome (LQTS), 14 healthy subjects of the same age serving as controls. Twelve patients had the typical history of syncopes or sudden cardiac death among family members; seven patients had a history of syncope, while four patients had been successfully resuscitated. None had associated cardiac disease. Among the group with LQTS the rate-corrected QT interval at rest was 498 + 56 ms, in the control group 412 +/- 30 ms (P < 0.005). Resting and maximal heart rates on exercise were similar in the two groups. The rate-corrected QT interval on exercise was significantly longer in the LQTS patients (P < 0.001). In the control group the maximal heart rate in the long-term ECG was significantly higher (144 +/- 28/min) than in the LQTS patients (128 +/- 17/min; P < 0.01). The long-term ECG recorded abnormal findings in five patients: torsade-de-pointes tachycardia in two, T-wave alternans in two, and bradycardia resulting from intermittent sinoatrial block in one. No abnormal findings were recorded in the control group (P < 0.03).

After extensive animal experiments a new method of high-frequency current coronary angioplasty (HFCA) via a specially developed catheter system was used in ten patients with haemodynamically significant coronary artery stenoses. In eight patients the stenoses affected the anterior interventricular branch (AIVB), in one patient each the circumflex branch and the right coronary artery, respectively. In nine patients the stenosis cross-section was reduced by at least 20% (from a mean of 91.9% +/- 5.8% to 52.6 +/- 17.5%). In three patients HFCA was followed by balloon angioplasty. The total number of applications per patient ranged from 3 to 12 (mean total duration of current flow: 3.9 +/- 1.0 s). There was only one severe complication, in a patient with subtotal AIVB occlusion after initially successful HFCA: balloon angioplasty successfully restored the lumen to the post-HFCA state. The new technique of HFCA is worthy of further development. It promises to be a valuable addition or alternative to balloon coronary angioplasty.

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.

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.

The investigations of ST-segment changes by Holter monitoring demonstrate asymptomatic and symptomatic episodes of myocardial ischemia, which may occur during daily activities. One factor, which is of great importance for the detection of silent myocardial ischemia during ambulatory monitoring, is the combination of the leads. Former studies showed that the analysis of two channels alone may not adequately detect silent myocardial ischemia. We therefore used a three-channel ambulatory ECG monitoring system with a new lead combination. The Holter monitoring results were correlated with the distribution of coronary stenosis detected by coronary angiography. In 54 patients with single coronary vessel disease and ischemic ST-segment depressions during exercise testing, standard Holter lead combination CM2/CM5 was extended by a bipolar Nehb D-like lead. Lead combination CM2/CM5 identified 23 patients (43%) with ST-segment depressions (total number of ischemic episodes = 372). Additional Nehb D-like lead identified 30 patients (55%) with ST-segment depressions (total number of ischemic episodes = 1048). The combination of leads CM2/CM5 and Nehb D raised the number of patients with documented ST-segment depressions to 33 of 54 (61%). Lead Nehb D showed the highest sensitivity for the detection of inferior wall ischemia (stenosis of the right coronary artery); nevertheless, this lead may not be regarded as specific for ST-segment alterations only caused by inferior wall ischemia. The correlation of ischemic ST-segment depressions during exercise testing (classified as anterior, inferior, or anterior and inferior type of ischemia) and documented ST-segment changes in the different Holter leads underline these results. A control group of 40 healthy volunteers demonstrated the high specifity of this new lead combination. In comparison with the standard lead combination CM2/CM5 for the detection of ST-segment changes, lead combination CM2/CM5 extended by a bipolar Nehb D lead is more sensitive for the detection of ST-segment alterations by Holter monitoring.

The feasibility and safety of outpatient coronary angiography were studied in 2,106 patients. Patients were discharged with a pressure dressing 2 h after the angiographic study. No complications occurred in 99.53% of all patients. Severe complications were seen in 10 patients (0.47%). 9 patients (0.43%) had to be admitted to hospital, either for immediate treatment (4 patients) or due to complications (5 patients). Our results revealed a very low complication rate for outpatient coronary angiography. The number and severity of complications following coronary angiography did not differ significantly between inpatients and outpatients. Therefore, outpatient coronary angiography can be considered as a safe and feasible diagnostic method which may help cut health care costs.

The Long QT syndrome (LQTS) is a relatively rare disorder. It has a major clinical impact as affected individuals are prone to syncope and sudden arrhythmogenic cardiac death. The LQTS comprises three groups of patients. The Jervell-Lange-Nielsen syndrome is characterized by an autosomal recessive pattern of inheritance and congenital neural deafness. The Romano-Ward syndrome shows an autosomal dominant pattern of inheritance and normal hearing. Patients with the sporadic form of LQTS have no evidence of familial transmission and have normal hearing. Imbalance of sympathetic cardiac innervation with predominance of the left stellate ganglion and an intrinsic myocardial defect leading to early afterdepolarization are the two pathogenetic mechanisms of LQTS discussed today. More recently a genetic basis for the Romano-Ward LQTS has been reported. The genetic linkage to the Harvey ras-1 gene provides the basis for a new hypothesis that an impairment of guanine nucleotide binding proteins is responsible for symptoms observed in LQTS. This paper discusses the genetic basis, pathology and pathophysiology of LQTS and tries to unify the different theories.

The aim of this study was to assess variability of ventricular late potentials (VLP) in patients with and without inducible ventricular tachycardia (VT), and the effects of antiarrhythmic drugs on VLP variability in the high-resolution electrocardiogram (HRECG). In 27 patients 90 s of unaveraged HRECGs were analysed before and 2 h after oral administration of 200 mg disopyramide, 400 mg mexiletine, 300 mg propafenone and 160 mg DL-sotalol. The duration of the QRS (QRSD) and the duration of the terminal low amplitude signal (LASD) was measured from each beat. Beat-to-beat variability was defined as standard deviation of the differences between consecutive beats. Patients with inducible sustained VT (n = 9) showed higher LASD variability than patients without inducible VT (12.3 vs 9.3 ms.beat−1, P < 0.01). Patients with VLP (n = 17), as defined by the signal averaged ECG, also had higher QRSD and LASD variability (11.8 vs 9.5 ms.beat−1, P < 0.05; 11.5 vs 8.2 ms.beat−1, P < 0.01, respectively) compared to those without VLP. All class I drugs lengthened QRSD and LASD in terms of the absolute values, but only propafenone increased QRSD and LASD variability (9.7 to 12.0 ms.beat−1, P < 0.01; 8.9 to 11.9 ms.beat−1, P < 0.01, respectively). In patients with inducible VT, sotalol decrease LASD variability from 14.3 to 9.3 ms.beat−1 (P < 0.05). We conclude that beat-to-beat VLP variability is increased in patients at a high risk of malignant arrhythmias. Further studies are needed to prove whether sotalol-induced reduction of beat-to-beat variability can serve as a non-invasive marker of antiarrhythmic efficacy.

BACKGROUND Calcification influences the outcome of various angioplasty techniques in the treatment of coronary artery disease. During angioscopic in vitro studies, we observed that dissections and perforations not caused by vessel bending frequently occurred at the boundary areas of plaque and adjacent vessel wall. This study investigated whether this is related to the distribution of calcific deposits. METHODS Postmortem excimer laser coronary angioplasty (308-nm XeCl) was performed in 51 stenotic coronary arteries. Twenty-three segments were further examined; these consisted of 11 perforations, six dissections, three segments with no ablative effect after the application of 20,000 laser impulses, and three successfully passed stenoses without complications. X-ray diffraction analysis and scanning electron microscopy were performed to detect calcium deposits and their spatial relationship to perforations and dissections. RESULTS X-ray diffractions analysis detected calcifications in 21 of 23 specimens. Postmortem angiography revealed calcifications only on 11 of 23 segments. Three of 11 perforations were located at the plaque border, as were three of six dissections. In all six complications at the plaque border, x-ray diffraction analysis revealed that the plaque border was identical with a border of calcium deposits. Eight of 11 perforations and three of six dissections could be explained by axis divergence between the laser catheter and the vessel orientation. CONCLUSIONS Contributing factors for perforations and dissections during excimer laser coronary angioplasty are axis divergence and the distribution of plaque calcification. More sensitive methods are needed to detect local vessel wall calcium in vivo.

The idiopathic long QT syndrome (LQTS) is an infrequently occurring disorder. It has major clinical impact as patients are prone to syncope, ventricular tachyarrhythmias and sudden arrhythmogenic cardiac death. This paper reports the value of ambulatory electrocardiogram (ECG) monitoring as a diagnostic tool to establish the diagnosis of LQTS. 14 patient with idiopathic LQTS were studied. The results were compared to those of 14 age- and sex-matched healthy control individuals. A 24-hour ambulatory ECG tracing was obtained in each individual. 5/14 patients with LQTS had pathological findings during ambulatory ECG monitoring (2 patients with episodes of torsade de pointes tachycardia, 2 patients with T-wave alternans and 1 patient with bradycardia due to an intermittent SA block), whereas all control persons had normal ambulatory ECG recordings (p < 0.03). Thus, ambulatory ECG recordings may contribute significant diagnostic information in patients with suspected LQTS.

A severe herpes simplex encephalitis with documented intra-cerebral lesions and brain edema was treated successfully with acyclovir and beta-interferon. The increase in intracranial pressure during the second week was well controlled by ICP monitoring. Life-threatening pressure peaks were avoided through the use of thiopental, osmodiuretics, TRIS, and lidocaine.

We present a general technique for hiding a classical bit in multipartite quantum states. The hidden bit, encoded in the choice of one of two possible density operators, cannot be recovered by local operations and classical communication without quantum communication. The scheme remains secure if quantum communication is allowed between certain partners, and can be designed for any choice of quantum communication patterns to be secure, but to allow near perfect recovery for all other patterns. The maximal probability of unwanted recovery of the hidden bit, as well as the maximal error for allowed recovery operations can be chosen to be arbitrarily small, given sufficiently high dimensional systems at each site. No entanglement is needed since the hiding states can be chosen to be separable. A single ebit of prior entanglement is not sufficient to break the scheme., 4 pages, RevTeX 4

We prove a conjecture by DiVincenzo, which in the terminology of Preskill et al. [quant-ph/0102043] states that ``semicausal operations are semilocalizable''. That is, we show that any operation on the combined system of Alice and Bob, which does not allow Bob to send messages to Alice, can be represented as an operation by Alice, transmitting a quantum particle to Bob, and a local operation by Bob. The proof is based on the uniqueness of the Stinespring representation for a completely positive map. We sketch some of the problems in transferring these concepts to the context of relativistic quantum field theory., 4 pages, 1 figure, revtex

We study separability properties in a 5-dimensional set of states of quantum systems composed of three subsystems of equal but arbitrary finite Hilbert space dimension d. These are the states, which can be written as linear combinations of permutation operators, or, equivalently, commute with unitaries of the form UxUxU. We compute explicitly the following subsets and their extreme points: (1) triseparable states, which are convex combinations of triple tensor products, (2) biseparable states, which are separable for a twofold partition of the system, and (3) states with positive partial transpose with respect to such a partition. Tripartite entanglement is investigated in terms of the relative entropy of tripartite entanglement and of the trace norm., 16 pages, RevTeX, 14 figures. Extends quant-ph/0003008 with additional results. Submitted to Phys.Rev.A

Although there have been reports of successful percutaneous transluminal coronary angioplasty (PTCA) and coronary artery bypass grafting (CABG) in elderly patients, few data are available on the optimal management of unstable angina in such patients. This study was therefore designed to identify the preferred revascularization strategy in patients with unstable angina over 75 years of age.Early and late results were evaluated for patients over 75 years with unstable angina undergoing PTCA (n = 51) or CABG (n = 53). The two groups were comparable with respect to age, sex distribution, clinical manifestation of symptoms, left ventricular ejection fraction and accompanying non-cardiac diseases. In the CABG group, significantly more patients had left main coronary artery stenosis (13 and 2%, respectively).Both PTCA and CABG treatment showed similar procedural success rates (91 and 94% respectively) and hospital mortality rates (4 and 6% respectively). Procedural complications were comparable regarding Q-wave myocardial infarction, stroke, renal failure and vascular complications. Patients undergoing CABG received significantly more blood transfusions than those undergoing PTCA (17 and 2% respectively). During follow-up, the mortality rate was comparable in both groups (4% with CABG and 8% with PTCA), but significantly fewer patients in the CABG group developed unstable angina (8 versus 21% in the PTCA group), fewer patients were readmitted to hospital for cardiac reasons (CABG group 17%, PTCA group 31%) and fewer patients needed repeat coronary interventions (CABG group 4%, PTCA group 18%).Both PTCA and CABG were comparable with regard to short- and long-term mortality, but CABG treatment was favourable with regard to clinical symptoms, readmission to hospital and repeat coronary interventions.

500 consecutive patients undergoing diagnostic coronary angiography were studied for vascular complications using either a conventional (n = 250) or a special mechanical device for compression dressing (n = 250). In both groups one case of arterial occlusion occurred. Using the conventional pressure dressing, we observed four pseudoaneurysms, whereas there were none in the special mechanical device dressing group (p0.05). In contrast, eight patients developed a deep vein thrombosis after mechanical device pressure dressing compared to only 1 venoust in the conventional dressing group (p0.02). Five patients, four of the eight patients with mechanical device dressing, suffered from clinical apparent pulmonary embolism (p = 0.1801). Thus, a mechanical device pressure dressing may decrease the number of arterial pseudoaneurysms but is associated with an increased risk of deep vein thrombosis and pulmonary embolism. Therefore, we recommend the use of the mechanical device pressure dressing only in selected patients with severe obesity.

Holter-monitoring and exercise-ECG can be employed for the detection of myocardial ischemia. Exercise-ECG is capable of detecting ischemias caused by physical activity. In contrast, Holter monitoring can detect episodes of myocardial ischemia independent of exertion, but possibly connected with other factors such as mental stress. In 60 patients (49 male, 11 female, mean age 55.1 years) with angiographically documented coronary artery disease (26 x 1-vessel, 21 x 2-vessel, 13 x 3-vessel diseases) exercise-ECG and ambulatory 24-h monitoring were performed (3-channel recordings, ST-segment analysis). The assessment of the exercise-ECG showed 31 out of 60 patients with pathological results. 34 patients had pathological ST-segment changes during Holter monitoring (56%). Since both methods detected different patients, a combination of these techniques is useful. The combination of Holter monitoring and exercise-ECG raised the sensitivity to 78% (47/60 patients). Different heart rates were found at the point of maximal ST-segment changes in exercise-ECG as compared to the episodes of ST-segment changes recorded by Holter monitoring. This finding clearly illustrates the fact that different pathophysiological mechanisms are causing myocardial ischemia in respective cases. Using the coronary arteriogram as standard, the sensitivity of the two methods was different. While both techniques could detect multi-vessel disease at a similar level, Holter monitoring was significantly more sensitive in detecting patients with single-vessel disease. Thus, exercise-ECG and Holter monitoring supplement each other in detecting myocardial ischemia. In the future, larger clinical trials will have to confirm these results.

In this study 97 patients with mitral regurgitation (age 62 +/- 11 years, 55 men, 42 women) quantified by angiography were studied using colour flow Doppler imaging of isovelocity surface areas in the flow convergence region proximal to the regurgitant orifice. The radii of the proximal isovelocity surface areas for the flow velocities of 28 and 41 cm/s were measured. A flow convergence region was imaged in 100% (96%) of the patients with Grade I/II or more and in 92% (64%) of the patients with Grade I mitral regurgitation for a flow velocity of 28 (41) cm/s. The radii of the proximal isovelocity surface areas correlated significantly with the angiographic grade in patients with sinus rhythm as well as atrial fibrillation. A correct differentiation of Grade I to II from Grade III to IV mitral regurgitation was provided in more than 90% of all patients for both flow velocities investigated. Assuming hemispheric proximal isovelocity surface areas, in 11 patients the regurgitant volumes from echocardiography (range: 2.6-241 (0.9-198) ml for a flow velocity = 28 (41) cm/s) correlated with, but considerably overestimated the values from cardiac catheterization (range: 1.4-72.5 ml) with r = 0.79 (0.82) (P < 0.01) and SEE = 57.9 (42.4) ml for a flow velocity of 28 (41) cm/s. It was concluded that colour flow Doppler imaging of the flow convergence region enables the diagnosis of mitral regurgitation and the differentiation between Grade I to II and Grade III to IV mitral regurgitation, but may be of little value in estimating the regurgitant volume, assuming a hemispheric symmetry of the proximal flow convergence region.

The value of long-term electrocardiographic (ECG) monitoring was assessed in 14 patients (8 males, 6 females; mean age 21 [17-30] years) with the idiopathic long QT syndrome (LQTS), 14 healthy subjects of the same age serving as controls. Twelve patients had the typical history of syncopes or sudden cardiac death among family members; seven patients had a history of syncope, while four patients had been successfully resuscitated. None had associated cardiac disease. Among the group with LQTS the rate-corrected QT interval at rest was 498 + 56 ms, in the control group 412 +/- 30 ms (P0.005). Resting and maximal heart rates on exercise were similar in the two groups. The rate-corrected QT interval on exercise was significantly longer in the LQTS patients (P0.001). In the control group the maximal heart rate in the long-term ECG was significantly higher (144 +/- 28/min) than in the LQTS patients (128 +/- 17/min; P0.01). The long-term ECG recorded abnormal findings in five patients: torsade-de-pointes tachycardia in two, T-wave alternans in two, and bradycardia resulting from intermittent sinoatrial block in one. No abnormal findings were recorded in the control group (P0.03).

The purpose of this study was to detect ventricular late fields recorded by a biomagnetic multichannel system in patients with ventricular late potential and to determine the site of these ventricular late fields non-invasively in three dimensions. Biomagnetic signals of sinus beats during a 5-min acquisition period simultaneously recorded by a 37-channel system Krenikon were averaged in all channels. Ventricular late fields were determined in each channel according to the algorithm of Simson for ECG data. For the localization process, baseline correction from the averaged non-filtered signals was performed at the end of the QRS complex under visual control. The single current dipole model within the homogeneous half-space was applied. Eight patients post myocardial infarction with ventricular late potentials (four with recurrent sustained ventricular tachycardia) and four healthy individuals were examined. In the normal subjects, no ventricular late fields were detected. However, ventricular late fields were found in all patients, and were localized in six patients within the border zone of myocardial infarction. In the four patients with ventricular tachycardia, a spatial coincidence of the site of origin of ventricular late fields and the site of origin of ventricular tachycardia determined by catheter mapping was found in two. It is concluded that magnetocardiography is able to detect ventricular late fields and can be used to determine their site of origin.

Life-threatening ventricular tachyarrhythmias are the main reason for sudden cardiac death in coronary heart disease. In the majority of survivors of cardiac arrest, malignant tachyarrhythmias generate from a structurally fixed arrhythmogenic substrate following myocardial infarction without evidence of acute ischaemia. Thrombolysis in acute myocardial infarction improves the electrical stability as elucidated by electrophysiological studies and the signal averaged surface ECG. In post-infarction patients, beta-blockers provide significantly beneficial effects on arrhythmic outcome, particularly in the presence of impaired left ventricular function, whereas calcium antagonists and vasodilators are of no affect or may worsen the prognosis. In survivors of myocardial infarction, the prophylactic use of class I antiarrhythmic agents, which are able to suppress frequent single or complex premature ventricular contractions, cause worsening of the prognosis due to their proarrhythmic properties. However, arrhythmia suppression by antiarrhythmic agents selects patients who are at very low risk for arrhythmic death. Pilot trials using class III antiarrhythmic agents suggest beneficial effect on the reduction of sudden death mortality. As regards secondary prevention of malignant tachyarrhythmias in survivors of ventricular tachycardia or fibrillation, there is controversy about the importance of Holter monitoring or invasive electrophysiological testing in the evaluation of drug efficacy. In patients with severely impaired left ventricular function, pharmacological treatment is of limited efficacy. Even in cases of significant suppression of spontaneous or inducible tachyarrhythmias documented by Holter recording or programmed ventricular stimulation, the arrhythmic outcome is considerably poorer, but it could be influenced by implantable defibrillators. Amiodarone, as a potential alternative to class I antiarrhythmic agents, particularly in patients refractory to conventional antiarrhythmic drugs, shows only limited effects on long-term outcome, which is in part caused by the toxicity of this agent. There is substantial need for new drugs without proarrhythmic properties and particularly for those that correct abnormalities of the automatic nervous system.

The idiopathic Long QT Syndrome is an infrequently occurring disorder. Affected patients usually show ECG alterations and are prone to syncope and sudden arrhythmic cardiac death. Adequate therapy with beta-blocking drugs may significantly improve the prognosis of affected patients. The early and precise diagnosis of the disorder therefore has major prognostic impact. This paper reports the diagnostic significance of standard ECG, exercise stress testing, ambulatory ECG monitoring, cold pressor test and Valsalva maneuver in 14 patients with Long QT Syndrome. The results were compared with those obtained in 14 healthy age matched volunteers. QTc duration was significantly longer in patients with Long QT Syndrome during standard 12-lead ECG at rest (489 +/- 55 ms versusvs.412 +/- 25 ms, p0.005), exercise stress test (490 +/- 39 ms vs. 409 +/- 18 ms, p0.001), cold pressor test (512 +/- 45 ms vs. 407 +/- 19 ms, p0.001), Valsalva maneuver (497 +/- 49 vs. 407 +/- 18 ms, p0.001), minimal heart rate during 24-h of ambulatory ECG monitoring (482 +/- 69 ms vs. 402 +/- 22 ms, p0.01) and maximal heart rate during Holter monitoring (460 +/- 47 ms vs. 411 +/- 27 ms, p0.005). Four of 14 patients with Long QT Syndrome had pathological findings during ambulatory ECG monitoring (two patients showed short episodes of asymptomatic torsade de pointes tachycardia, one patient had an intermittent SA-Block, and one patient showed T-wave alternans). All healthy volunteers had normal ambulatory ECG recordings (p0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Electrical events of the heart can be detected by the conventional surface ECG, however, only depolarization and recovery of the atria and ventricles and the atrio-ventricular conduction delay (P-Q interval) are reflected by the corresponding signals, the P wave and the QRS complex. The activity of the sinus node itself and the His-Purkinje system is buried within the baseline noise because on the body surface their amplitudes are only in the microvolt range. Prolongation of intraventricular conduction of larger myocardial areas can be discovered by the typical hemiblock or bundle branch block patterns of ventricular de- and repolarization, whereas delayed activation of smaller areas of ventricular myocardium, e.g. in the neighborhood of an infarcted area or in right ventricular dysplasia, will be invisible within the conventional surface ECG due to the small amplitude (microvolt level) of the signals of interest1.

The idiopathic long QT syndrome (LQTS) is an infrequently occurring disorder. Affected patients may have electrocardiographic alterations and are prone to syncope and sudden arrhythmogenic cardiac death. Adequate therapy may improve the prognosis of affected patients significantly. Therefore the early and precise diagnosis of LQTS has major prognostic impact. This study reports the diagnostic significance of standard electrocardiographic techniques and autonomic maneuvers in 14 patients with LQTS. The findings are compared with those of 14 healthy age-matched control persons. QTc duration was significantly longer in patients with LQTS during standard 12-lead electrocardiography (489 +/- 56 vs 412 +/- 30 ms, p < 0.005), exercise stress testing (490 +/- 38 vs 409 +/- 18 ms, p < 0.001), cold pressor testing (512 +/- 45 vs 407 +/- 19 ms, p < 0.001), Valsalva maneuver (497 +/- 49 vs 407 +/- 19 ms, p < 0.001), minimal heart rate during 24-hours of ambulatory electrocardiographic recording (482 +/- 69 vs 402 +/- 22 ms, p < 0.01) and maximal heart rate during Holter monitoring (460 +/- 47 vs 411 +/- 27 ms, p < 0.005). Four of 14 patients with LQTS had pathologic findings during ambulatory electrocardiographic monitoring (2 patients with short episodes of torsades de pointes tachyarrhythmia, 1 patient with intermittent sinoatrial block, and 1 patient with intermittent TU-wave alterations), whereas all control persons had normal ambulatory electrocardiographic recordings (p < 0.05). Thus, noninvasive standard electrocardiographic techniques in combination with autonomic maneuvers may contribute significant information for a precise diagnosis in patients with suspected LQTS.(ABSTRACT TRUNCATED AT 250 WORDS)

The experimental production of a myocardial infarction (MI) in the dog was achieved adopting a new catheter technique. After induction of the MI, a variety of arrhythmias appeared and were classified according to the Lown-classification as more or less severe. The therapy was achieved with antiarrhythmics class 1-111 (Vaughn-Williams classification) for late premature ventricular beats or couplets. Sinus tachycardia was often terminated by occular or sinus carotis pressure or a new selective sinus blocking agent. Results showed Amiodarone to be the drug of choice in the treatment of severe arrhythmias (Lown IV and V) like triplets or salves of extrasystolies. Ventricular fibrillation always resulted in the death of the animal, because fibrillation was not convertible by direct current cardioversion, endovenous injection of Lidocaine or even internal cardiac massage. The registration of hemodynamic parameters (left ventricular end diastolic pressure, wedge pressure, pulmonary and aortic pressure) was shown to be important in controlling the therapy, as well as blood gas and electrolyte analysis.

Summary: This report describes the usefulness of echocardiography in the differential diagnosis of acute cardiovascular events. In a 66-year-old patient with known aortic stenosis and mitral valve prothesis, who suddenly deteriorated with severe dyspnea, a thrombus within the pulmonary artery could be detected with 2-D echo. Pulsedwave Doppler disclosed the resulting flow-velocity disturbances.

In diffuse small-vessel coronary heart disease, heart transplantation may be indicated for intractable angina. As an alternative, a free striated muscle flap can constitute a source of neovessels. Those extraintracardial collaterals develop only 4 weeks after transplantation of the flap as shown by the following experiments with seven dogs. In those animals a myocardial infarction of the anterior wall was selectively produced by the Judkins technique for the injection of Sephadex microspheres. Four weeks later a free pectoralis muscle flap was transplanted onto the anterior wall of the heart. Arterial blood supply was achieved by anastomosis with the internal mammary artery. The venous flow was directed into the right atrium. Six weeks after surgery the patency of the anastomosis was studied by angiography, which showed patency in all animals. Pathologic examination of the hearts revealed a prominent capillary network penetrating into the underlying myocardium. Corrosion cast preparations showed even further penetration of the capillary network into the noninjured parts of the myocardium. Thus myocardial revascularization could be achieved by transplantation of a skeletal muscle on the heart.

Percutaneous excimer laser coronary angioplasty (ELCA) was performed in a first group of 20 patients with stable angina pectoris caused by significant coronary stenosis, and long-term follow-up was evaluated. Prototype 4 to 5.5 French multifibre catheters with 18-20 quartz fibres of 100 microns diameter, concentrically arranged around a central lumen for taking up a guide wire, were coupled to a commercial XeCl excimer laser. Energy was delivered at a wavelength of 308 nm with a pulse duration of 60 or 120 ns. Operating at a repetition rate of 20 Hz, mean energy transmission was 13.4 +/- 6.8 mJ per pulse. In all but one patient the lesion could be passed by the catheter. Percent diameter stenosis decreased from 77.1 +/- 10.8% to 53.1 +/- 11.8% after ELCA. Complications were frequently observed, intracoronary thrombus formation in eight instances, dissection in six patients and spasm in five cases, causing total vessel occlusion in five procedures. All complications could be managed efficaciously by thrombolytic and vasodilating drugs and/or balloon angioplasty. Subsequent PTCA was performed in case of complication or insufficient stenosis reduction after ELCA in 18 patients with adequate results (residual stenosis, 28.5 +/- 10.2%). Long-term follow-up angiography, which could be performed in 16 of 19 laser treatments, demonstrated significant restenosis in only three patients. Our preliminary results suggest that, using ELCA, ablation of atherosclerotic lesions is feasible in most cases. However, compared with PTCA, stenosis reduction is significantly less, and the acute complication rate is much higher. Thus, further improvements of the catheter system are necessary in order to realize the advantages of excimer laser ablation, which can be demonstrated by experimental studies.

Gestielte oder freie Muskellappen sind ein bewahrtes plastisch-chirurgisches Vorgehen in der Deckung groserer und schlecht heilender Gewebsdefekte. Das Einsprossen von Ca- pillaren seitens des Muskeltransplantates in ein minderperfundiertes Gewebsareal fordert die Bildung von Granulationsgewebe und fuhrt zur Ausheilung des Gewebsdefektes. Bei der Kardiomyoplastie, der Transplantation des gestielten Latissimus dorsi zur Stutzung der Pumpfunktion kardiomyopathischer Herzen, wurde als Nebenbefund eine Einsprossung von Capillaren seitens des transplantierten Muskels ins Myokard beschrieben [2, 4, 5]. Inwieweit diese Neogefase persistieren und ob sie zu einer Myokardrevascularisation beitragen konnen, haben wir am Hundeherz nach Transplantation eines freien Skelettmuskellappens untersucht. Um einen Gewebsdefekt unter dem Transplantat zu provozieren, wurde bei den Tieren ein Vorderwandinfarkt induziert. 4–20 Wochen nach Muskeltransplantation wurden die Herzen mittels Gefasausgussen sowie histologisch und elektronenmikroskopisch untersucht.

The present study was undertaken to measure normal aortic blood velocity profiles by means of continuous wave Doppler echocardiography from apical and suprasternal positions in 40 healthy adults. The profiles in the ascending aorta were measured from both positions, whereas the profiles in the descending aorta were measured only from the suprasternal position. The highest values for the maximal flow velocities were found in the ascending aorta from the suprasternal position (1.28 +/- 0.18 m/s), the lowest values for the maximal flow velocities were found in the descending aorta (1.17 +/- 0.22 m/s). This trend was also found for the mean velocity values. As to the time parameters, a longer acceleration time for the descending aorta was remarkable (106 +/- 24 ms), whereby the mean values for the ejection time for the descending aorta (308 +/- 25 ms, suprasternal: 320 +/- 30 ms). The highest values for the acceleration were found in the ascending aorta (suprasternal: 1526 +/- 531 cm/s2, apical: 1422 +/- 330 cm/s2) and the lowest values in the descending aorta (1208 +/- 378 cm/s2). Regarding the maximal velocity index there was no significant difference for the maximal values between the different transducer positions. The results of the regression analysis showed only a weak correlation of the maximal velocity values in the different transducer positions. This means that for follow-up examinations only those values should be used that were obtained from the same transducer position.

In 1977 Andreas Gruntzig performed the first balloon angioplasty in a patient with a critical LAD stenosis [5]. Since that time considerable improvements have been achieved both with the technique itself (steerable guide wires, low profile and super low profile balloons with steerable or fixed guide wires, monorail technique etc.) and the skills of the angio-plasters. Therefore balloon angioplasty in the 1990s has become a standard technique for reduction of significant coronary artery stenoses in patients with coronary heart disease [1,5,9,14]. The acute and longterm results of balloon angioplasty now seem to be standardized worldwide: acute success rate: 80–90%, depending on the coronary artery to be treated and the type of coronary artery lesion; rate of acute complications: about 10%, and that of emergency bypass: 2–5% [1,2], recurrency rate at 3 months: 15–30%, and at 6 months post-treatment about 40–50%.

Since catheter or surgical techniques for ablating the arrhythmogenic substrate in patients with SVT due to accessory pathways or those with VT are now available, exact localization of the substrate is mandatory. We report preliminary results of two new non-invasive techniques for localizing either the site of earliest ventricular contraction using ISPECT, or the site of initial ventricular depolarization by magnetocardiography (MCG) in WPW syndrome and in VT patients. Thirteen patients with WPW syndrome and 8 patients with sustained VTs were studied with ISPECT. In 9/13, comparative catheter mapping data were available. Two patients had two Kent bundles. 13/15 Kent bundles could be localized by ISPECT. In 5/9 patients the area of Kent bundle insertion was identical with ISPECT and catheter mapping, in 3 correlation was fair, and in 2 patients with 2 Kent bundles ISPECT failed to localize their insertion. In 3/8 patients with VT catheter mapping could not be performed for hemodynamic reasons. In 2/5 patients the area of VT focus was identical with both methods, in one patient it was adjacent to each other, and in 2/5 patients a larger anatomic distance of the focus was found with both methods. In 3/7 patients with WPW the MCG showed the site of Kent bundle insertion, which was identical to that seen by catheter mapping. In one patient the area was adjacent, and in 3 more distant from the site determined by catheter mapping. In 1/2 patients with 2 Kent bundles, one of these could be detected by MCG. In 1/3 patients with VT, the site of VT focus was identical with both methods, but in the remaining two a distance of 3–4 cm was observed between the area seen with MCG and that with catheter mapping. In 4 further VT patients with stable and uniform ventricular late potentials, ventricular late magnetic activity was found with different QRS lengths within the single MCG channels. From our results we conclude that both ISPECT and MCG seem to become very promising non-invasive techniques for localizing ectopic ventricular depolarization in WPW syndrome and VT patients. However, these methods have to be refined, improved and validated by further systematical studies.

The purpose of this article is to review the success rates and complication rates of balloon angioplasty, the conventional angioplasty technique, and newer techniques such as laser, atherectomy, and radiofrequency angioplasty. The main problem of such an analysis is the inhomogeneity of the so-called new interventional techniques in terms of both technical principles (thermal angioplasty by laser or radiofrequency, photoablation, mechanical atherectomy) and stage of development (Table 1). With some of the new techniques such as the Simpson atherectomy device [68, 76] clinical studies of about 500 patients are available, allowing a preliminary comparison with balloon angioplasty; other techniques such as radiofrequency angioplasty [34] have been clinically performed only in small patient groups.

At time, balloon angioplasty is the well established standard procedure for nonsurgical treatment of coronary stenosis with a success rate of about 90 to 95%. The major limitations of balloon angioplasty such as poor results in recanalisation of chronic obstructed arteries, in the treatment of diffuse atherosclerotic vessels and the high incidence of restenosis [1, 3, 13] are the reasons for the development of alternative techniques like atherectomy, rotational atherectomy and other methods of mechanical revascularisation [4, 12, 18], radiofrequency angioplasty [8], hot balloon angioplasty [19] and different methods of laser applications in peripheral and coronary arteries [6, 19, 20, 21].

Pulsed submicrosecond excimer laser irradiation provides the potential for debulking atherosclerotic material without significant thermal injury to the adjacent vessel wall. Considerable progress has been made during the last few years as to the quality of the optical fibers, the design of laser-fiber coupling devices and catheter systems, and, in particular, the development of long-pulse excimer lasers. With these improvements in technology, excimer laser angioplasty has become technically feasible, but most patients require subsequent balloon angioplasty to obtain an adequate final result. There are a number of major impediments to the clinical use of the excimer laser for angioplasty. Among those are problems relating to (1) the heterogenous ablative characteristics of plaque, (2) the potential mismatch between the open lumen of the vessel and the amount of atherosclerotic material that can be removed by the laser, and (3) the failure of the cutting tip of the catheter to engage in excentric lesions. These issues need resolution before excimer laser angioplasty can become an alternative to balloon angioplasty. Minor points include the distal embolization of the particulate debris and the thrombogenicity of the lased vascular surfaces.

For more than 50 years investigators have been attempting to accurately describe the human coronary pathologic anatomy. The modern technique of coronary arteriography was introduced by Sones and Shirley [20] in 1959; they discovered that by selective transbrachial coronary cannulation one could safely opacify the left and right coronary artery in man. Other selective angiographic techniques such as the percutaneous transfemoral artery approach described by Judkins using different pre-formed catheters for specific procedures [11] quickly developed.

The most notable limitations of balloon dilatation, acute vascular occlusion with a rate of 3 to 5% and restenosis rate of 20 to 40%, appear at least partially attributable to the mechanism of luminal widening--tearing of the intima and plastic restructuring of plaque material. Alternative angioplasty methods, with the exception of stent implantation, are based on the concept of rendering plaque material, by excision and ablation, with a smoother and less thrombogenic interior surface and to lower the risk of renewed proliferation. Plaque material is removed in three ways: mechanical, by excision; thermically, by laser with relatively low energy density or by high-frequency alternating current; non-thermically, by photoablation with laser of very high energy impulse density. High-frequency alternating current as an energy source for thermic angioplasty is used in four technically different forms of application (Table 1): as indirect or direct high-frequency angioplasty in the scope of the "spark erosion" technique and for heating a balloon during balloon dilatation to achieve thermofusion of the tissue for stabilization of the angioplasty results. With indirect hot-tip high-frequency angioplasty the high-frequency alternating current is employed to rapidly heat an olive-shaped fully isolated metal tip with an integrated resistor, plated with gold to avoid adhesion of thrombotic material. The heat emitted is directed radially. The currently-available system consists of a 20-Watt high-frequency generator with 5 MHz. On application of 10 Watts to tissue in water at 37 degrees C, the temperature achieved at the catheter tip is 130 to 140 degrees C.(ABSTRACT TRUNCATED AT 250 WORDS)

Sudden cardiac death occurs in the Federal Republic of Germany with an incidence of 60,000 to 90,000 per year. Ambulatory ECG monitoring has demonstrated that in about 80% of such events, the heart rhythm before and during sudden cardiac death shows ventricular tachycardia leading to ventricular fibrillation and circulatory standstill. From experimental studies it is known that the substrate for precipitation of the ventricular arrhythmia is localized injury in myocardial tissue with conduction delays and conduction blocks resulting in inhomogeneous spread of the impulse between normal and injured myocardium enabling the existence of an electrical re-entry circuit. Anisotrophy, that is differing velocities of conduction parallel and perpendicular to fiber direction as well as dispersion of repolarization appears responsible for propagation of the circuit. Because of the delayed impulse spread, the late depolarization after the end of the QRS complex can be detected in the ECG as ventricular late potentials by means of high resolution systems. Ventricular late potentials may be regarded as indicative of increased electrical vulnerability of the ventricles. Prevalence of ventricular late potentials: In our own studies using the signal-averaged ECG technique, ventricular late potentials were found most frequently in patients with coronary artery disease and only in 6/100 healthy subjects, in 5/30 patients with dilated cardiomyopathy, in none of 30 patients with aortic stenosis or ten with "small vessel disease". With continuously-registered high resolution electrocardiography but not with the signal-averaged ECG, patients with dilated cardiomyopathy or QT-syndrome can be found to have labile, intermittent ventricular late potentials. In patients with coronary artery disease, the number of those in whom ventricular late potentials can only be detected with continuously-registered high resolution ECG in addition to signal-averaged technique lies between 6 and nearly 30%. With respect to frequency analysis of the ST-segment, which is based on the hypothesis that the fractionated signals in arrhythmogenic areas are of higher frequency than the normal low frequency signals of the ST-segment in normal myocardial areas, there is only limited experience and no data from larger collectives.(ABSTRACT TRUNCATED AT 400 WORDS)

Patients suffering from the long QT syndrome (LQTS) are threatened by sudden arrhythmic cardiac death. This case report describes a new therapeutic approach to ventricular tachyarrhythmias refractory to oral pharmacological treatment (propranolol + phenytoin) using a drug-reservoir-pump system for the pharmacologic blockage of the left stellate ganglion. (Chest 1990; 97:250-51)