Predictors of Ventricular Tachvcardia Inducibility in Programmed Electrical Stimulation and the Effectiveness of Serial Drug Testing: Polish Multicenter Study

WNUK-WOJNAR, A.M., ET AL.: Predictors of Ventricular Tachycardia Inducibility in Programmed Electrical Stimulation and Effectiveness of Serial Drug Testing: Polish Multicenter Study. In 100 patients with IHD and complex ventricular arrhythmias, programmed electrical stimulation was performed using up to three extrastimuli at sinus rhythm, and paced 100, 120, and 140 beats/min delivered from the RV apex, outflow tract or the LV with ventricular mapping to evaluate late potentials (LP) in 41 patients. Sustained monomorphic VT (SMVT) was provoked in 91% of 42 patients with a history of VT/VF, p < 0.001, all five patients had SMVT in 24-hour ECG, p < 0.005, and 91% of 21 patients with LV dyskinesis, p < 0.01. After depolarizations were found in 62% of 21 patients with a history of VT, in 58% of 31 patients with inducible VT, p < 0.01 and in five of six patients with LV dyskinesis. In patients with inducible VT, LP had a higher amplitude (105 ± 35 vs 60 ± 47 µV) and were more delayed (202 ± 96 vs 133 ± 75 msec) than in noninducible patients. In 17 patients, serial drug testing was performed after oral administration using mexilitene, disopyramide, chinidine, propafenone, sotalol, and amiodarone. If one drug was tested, the therapy efficacy was 25% if two drugs-60%, and if three drugs-75%. In eight patients, VT was inducible in all tests, but in only one of these patients chronic antiarrhythmic therapy was not effective. We conclude that the most important predictors of VT inducibility are a history of VT or 24-hour ECG, and LV dyskinesis. Serial drug testing is efficient only when many drugs are tested, but even if VT is inducible, it does not exclude the possibility of a good clinical outcome in chronic therapy.     

Transesophageal Programmed Atrial Pacing as a Method of Selecting Patients with Sick Sinus Syndrome for Permanent Atrial Pacing

Many recent studies have shown transesophageal programmed atrial pacing (TP) as a very practical, safe and convenient way for assessment of sinus node function and AV conduction. On the other hand, permanent atrial pacing is known to be superior to ventricular pacing due to arrhythmogenic and hemodynamic reasons. This is the reason why we decided to use TP as a method of choosing patients with sick sinus syndrome (SSS) for permanent atrial pacing. Sixty-three patients with symptomatic (58) and asymptomatic (5) SSS in a variety of clinical situations were examined in this way. The following electrophysiological features were examined: sinus cycle length, sinus node recovery time as well as corrected time, secondary pause after overdrive stimulation, sinoatrial conduction time, Wenckebach point, induction of supraventricular arrhythmias by S1, S2, S3 programmed stimulation and burst pacing. Patients with abnormal parameters were examined once more after intravenous atropine 0.2 mg/kg to evaluate parasympathetic component. Standard 12-lead ECG was performed in ail, and Holter monitoring in most of patients.
Twenty-six patients were candidates for permanent AAI pacing. Failures occurred in eight patients usually due to low P wave amplitude and electrode instability. Eighteen patients received AAI pacing systems: eight with brady-tachycardia syndrome, nine with brady-arrhythmia and one with sinoatrial block. In the follow-up of 5–28 months in one patient occurred high degree AV block (11°) during digitalis therapy. Reduction of doses made this block disappear. Examination of Wenckebach point and possibility of inducation of supraventricular lachyarrhythmias in cases of atrial overexcitability are particularly useful in selecting patients for AAI pacing. (PACE, Vol 11 November Part II 1988)     

Analysis of Circadian Distribution of Premature Ventricular Contractions in Patients After Heart Transplantation

The aim of our study was to analyze circadian distribution of premature ventricular contractions (PVC) and its coupling interval (CI) in patients after orthotopic heart transplantation (HTx). Forty-two patients (5 females, 37 males) were monitored from 2 weeks to 5 years after HTx; 180 24-hour Holter ECG studies were performed. All recordings were divided into two groups: group I, within 1 month after HTX; and group II, after 1 month. Patients with more than 250 PVC/24 hours were selected for distribution of PVC and CI evaluation. Conclusions : Ventricular arrhythmias occur frequently in patients after heart transplantation. In patients with high Lown scale arrhythmias low occurrence (< 250/24 hours) of PVC was frequently observed (IVa: 81.8%; IVb: 84.7%). Similar patterns of circadian distribution (CD) of PVC and CD of HR in denervated heart after HTx suggest the influence of circulating catecholamines on their occurrence.     

Late caliceal fistula after kidney transplantation

Caliceal fistula is a rare urological complication that can occur usually shortly after kidney transplantation (KTx). The occlusion of the renal accessory artery with subsequent necrosis of the kidney pole is the most common cause of the fistula development. We report a case of a 57-year-old man with reconstruction of two accessory renal arteries by anastomosis to the side of the main artery during graft placement complicated by late caliceal fistula, managed surgically. Directly after KTx good kidney graft function (serum creatinine concentration 151 micromol/L) was observed. The patient noticed protuberance and pain in the kidney graft area 5 months later. Diagnostic imaging revealed moderate urostasis and liquid collection in the region of the lower graft pole. Administration of a contrast medium through the inserted drain visualized a fistula of a lower renal calyx and ureteric stenosis. Percutaneous drainage was applied with subsequent stop of diuresis through the urethral catheter. During the surgery, the resection of a lower kidney graft pole necrosis was performed, with the closure of caliceal fistula. Simultaneously double pigtail ureteric stent was inserted. After the next two months the pigtail catheter was removed, and neither urostasis in the kidney graft nor liquid collection in the perigraft area were observed. The exceptionality of the case is the late caliceal fistula occurrence. We may only speculate, why it happened 5 months after KTx. The thrombosis of stenosed accessory artery is the most probable cause.     

Predictive Value of Various Types of Ventricular Response to Programmed Ventricular Stimulation: Relation to Holter Monitoring

The study was performed to determine the predictive value of programmed stimulation for identification of pts with ventricular arrhythmias: 75 patients were studied by means of 24-hour ambulatory ECG (24 ECG) and programmed right (in some patients also left) ventricle stimulation at sinus and two or three pacing rates using two (standard) and three extrastimuli or burst stimulation (extensive protocol). Lown classes 0.1–3 and 4a–4h were observed in 24 ECG in 35, 14, and 26 patients, respectively. In programmed stimulation 1–6 repetitive ventricular responses (RVR) were found in 56 pts, nonsustained ventricular tachycardia in 11 and sustained ventricular tachycardia in 21 pts. High incidence of induced VT was found in pts with complex ventricular arrhythmia in 24 ECG, 81% of this group, in all but six pts only standard protocol was used. The 1–6 RVR were observed in almost 40% of pts without any arrhythmia. Conclusion; Only VT induction is a useful index for high risk patients.     

Does the Change of the Polarity of Electrodes Influence the Results of Transoesophageal Bidirectional DC Cardioversion?

The aim of the study was to compare the bidirectional transoesophageal DC cardioversion (BOC) with unidirectional transoesophageal DC cardioversion (UOC) and to evaluate, if the reversion of the polarity of electrodes alters the effectiveness and the amount of energy during BOC. UOC was attempted in 300 patients (pts) with atrial fibrillation (AF) and BOC in 241 pts with AF. In UOC mode shocks were delivered between the 4-ring oesophageal electrode (cathode) and the chest pad (anode) positioned in the precordial region. In BOC shocks were delivered between the same oesophageal electrode and two chest pads joined with each other, positioned on both sides of the sternum. First 147 pts were cardioverted with the oesophageal electrode as a cathode, next 94 with an anode in oesophageal position. The effectiveness of both modes (UOC and BOC) was very high, however in pts with chronic AF success rate was better in BOC approach (82% vs 100%). BOC, compared with UOC, allowed to decrease the threshold defrbrillation signifrcantly: in pts with recent onset of AF from 61,5 J to 33,3 J and in pts with chronic AF from 99,8 J to 75,2 J. In pts with long standing AF the reduction of the defrbrillation threshold was statistically not significant (from 68,6 J to 50,6 J). The effectiveness of BOC was also very high independently of the polarity of electrodes. The change of the polarity did not affect the minimal and total successful energy of shocks, too. In pts with oesophageal electrode as a cathode defibrillation threshold was 48,4 J and in pts with the anodal electrode 43,7 J. In conclusions we found BOC as a very effective method in pts with AF. Defibrillation threshold in BOC is lower than in UOC and the polarity of electrodes does not influence the success rate and successful energy.     

Effects of CPAP treatment on psychological status in patients with severe obstructive sleep apnoea

The aim of this study was to evaluate the effects of nocturnal continuous positive airway pressure (CPAP) breathing on the emotional status and cognitive function in 20 patients with severe obstructive sleep apnoea (OSA) (mean±SD apnoea/hypopnoea index=67±16, mean overnight arterial oxygen saturation=83±10%). Psychological tests were performed before, after three, and after twelve months of CPAP treatment. At initial investigation, amongst cognitive functions, the most disturbed were concentration and recent memory. The majority of subjects demonstrated increased mental stress, depression, and anxiety. Anxiety correlated with AHI ( r =0.68). Mental stress correlated with AHI ( r =0.56) and deficiency of Stage 2 NREM sleep ( r =−0.55). CPAP treatment resulted in significant improvement in cognitive function; concentration, recent verbal, visual and spatial memory were already seen at three months. No improvement in IQ and in emotional status after three months and one year of treatment was found. It is concluded that in patients with severe OSA CPAP treatment results in a significant early improvement in cognitive function but not in emotional status.     

Increased coated-platelet levels in chronic haemodialysis patients

Aim: To determine if levels of coated‐platelets, which are potentially pro‐thrombotic, are increased in end‐stage renal disease patients on haemodialysis, a condition associated with high cardiovascular disease risk. Methods: In a cross‐sectional observational study, coated‐platelet levels were measured by flow cytometry in 25 end‐stage renal failure haemodialysis patients and 25 controls without renal disease. Associations between coated‐platelet levels and clinical and biochemical factors relevant to renal and cardiovascular disease were evaluated. Results: Mean ± SD coated‐platelet levels were higher in the dialysis group than in the control group (39.3 ± 14.3% vs 30.9 ± 10.3%, P = 0.02). The number of subjects with high coated‐platelet levels (>40%) was larger in the dialysis than in the control group (13/25 vs 4/25, χ² test, P = 0.007). On univariate analysis, coated‐platelet levels correlated with serum C‐reactive protein levels in renal failure (r = 0.47, P = 0.02) and inversely with white cell count in the control group (r = ?0.60, P = 0.001). Coated‐platelet levels were higher in dialysis patients reporting alcohol abstinence than among those reporting ‘social’ drinking (44.3 ± 12.6 vs 28.8 ± 13.5%, P = 0.01). Age, gender, body weight, smoking, diabetes, lipid levels and lipid‐lowering drugs were not associated with coated‐platelet levels (all P > 0.05). Conclusion: Coated‐platelet levels are increased in haemodialysis patients relative to subjects with normal renal function, and are related to inflammation and alcohol abstinence. Other vascular risk factors, such as smoking, lipids and diabetes, were not related to coated‐platelet levels. Coated‐platelets may be implicated in the increased thrombosis and vascular risk in end‐stage renal disease.