High incidence of atrial fibrillation after successful catheter ablation of atrioventricular nodal reentrant tachycardia: a 15.5-year follow-up

Atrioventricular nodal reentrant tachycardia (AVNRT) is the most common type of supraventricular tachycardia. Slow pathway (SP) ablation is the treatment of choice with a high acute success rate and a negligible periprocedural risk. However, long-term outcome data are scarce. The aim of this study was to assess long-term outcome and arrhythmia free survival after SP ablation. In this study, 534 consecutive patients with AVNRT, who underwent SP ablation between 1994 and 1999 were included. During a mean follow-up of 15.5 years, 101 (18.9%) patients died unrelated to the procedure or any arrhythmia. Data were collected by completing a questionnaire and/or contacting patients. Clinical information was obtained from 329 patients (61.6%) who constitute the final study cohort. During the electrophysiological study, sustained 1:1 slow AV nodal pathway conduction was eliminated in all patients. Recurrence of AVNRT was documented in 9 patients (2.7%), among those 7 patients underwent a successful repeat ablation procedure. New-onset atrial fibrillation (AF) was documented in 39 patients (11.9%) during follow-up. Pre-existing arterial hypertension (odds ratio 2.61, 95% CI 1.14–5.97, p = 0.023), age (odds ratio 1.05, 95% CI 1.02–1.09, p = 0.003) and the postinterventional AH interval (odds ratio 1.02, 95% CI 1.00–1.04, p = 0.038) predicted the occurrence of AF. The present long-term observational study after successful SP ablation of AVNRT confirms its clinical value reflected by low recurrence and complication rates. The unexpectedly high incidence of new-onset AF (11.9%) may impact long-term follow-up and requires further clinical attention.

Impaired Fibrinolytic Capacity Predisposes for Recurrence of Venous Thrombosis

The fibrinolytic capacity of 121 patients with a history of venous thrombosis and/or pulmonary embolism was studied by venous occlusion technique, at earliest 3 months after the last thromboembolic episode. After discontinuation of oral anticoagulation treatment the clinical course of the patients was followed and new thromboembolic episodes were noted. During the observation period of 56 ± 18.8 months 45 of 121 patients experienced recurrence of thrombosis. The recurrence-rate was significantly lower in patients with a post-occlusion ELT shorter than 60 min (4.8%/year) than in patients with an ELT longer than 60 min (10.3%/year). It is concluded that the fibrinolytic capacity is a useful parameter for determining the risk of recurrence in patients with venous thrombosis.

Benign prognosis of early sinus node dysfunction after orthotopic cardiac transplantation

Previous reports raised concern about the prognosis of patients with sinus node (SN) dysfunction after cardiac transplantation and led to a low threshold for permanent pacemaker (PM) placement at most institutions. The present study addresses the survival in patients with normal and impaired post operative SN function and the effect of permanent pacing with respect to overall and cardiac mortality. There were 120 patients with normal (corrected SN recovery time < 520 ms, group I) and 47 patients with imparied SN function (corrected SN recovery time > 520 ms and/or sinus arrest +/- escape rhythms). Pacing support was deemed unnecessary in 23 of 47 patients with SN dysfunction (group II; asymptomatic SN bradycardia and corrected SN recovery time 3,812 +/- 5,800 ms) while a total of 24 patients had PM placement a mean of 29 +/- 44 days after transplantation (symptomatic bradycardia or absence of sinus rhythm at discharge, group III). Patients were followed for a mean of 46.7 months. Thirty-five deaths occurred during the study period. Sixteen deaths were cardiac but none were causally related to the SN dysfunction (graft failure due to rejection or atheropathy n = 14; myocardial infarction n = 2). Four of these cardiac deaths were sudden and all occurred in the presence of widespread structural abnormalities (rejection/vasculopathy/myocardial infarction). SN dysfunction was not related to overall (P = 0.25) or cardiac mortality (P = 0.33). Regarding either endpoint, patients who had permanent PM placement did no better than their unpaced counterparts in group II (P = 0.53 and P = 0.33, overall and cardiac mortality, respectively). Likewise, survival did not differ between groups I and III for either endpoint (P = 0.77, P = 0.65, respectively). These data suggest that patients with mild SN abnormality, who are in sinus rhythm at the time of discharge, can be followed by observation without specific therapy.

Significance of morphological abnormalities detected by MRI in patients undergoing successful ablation of right ventricular outflow tract tachycardia

BACKGROUND

MRI can demonstrate subtle morphological changes of the right ventricle in patients with idiopathic right ventricular outflow tract tachycardia (RVOT). The present study examines the incidence and significance of right ventricular (RV) abnormalities detected by MRI with respect to the site of successful radiofrequency catheter ablation of the clinical tachycardia.

METHODS AND RESULTS

The study population comprised 20 patients (mean age, 40+/-12 years) undergoing elimination of recurrent RVOT by radiofrequency catheter ablation. MRI studies were performed before ablation to assess RV volumes and function, as well as structural abnormalities of the RV myocardium. Ten healthy age- and sex-matched subjects served as control subjects. The successful ablation sites, as documented by radiographs of the catheter position, were compared with MRI findings. Patients with RVOT showed no difference in respect to RV volumes and ejection fractions compared with control subjects. Whereas RV abnormalities were limited to prominent fatty deposits of the right atrioventricular groove extending into the inlet portion of the RV wall in 2 of 10 control subjects, MRI studies demonstrated morphological changes of the RV free wall in 13 (65%) of 20 patients with RVOT, including presence of fatty tissue (n=5), wall thinning (n=9), and dyskinetic wall segments (n=4). Eight of these patients had additional fat deposits, thinning, or a saccular aneurysm in the RV outflow tract, corresponding with the ablation site in 6 patients.

CONCLUSIONS

In RVOT, structural abnormalities of the right ventricle can be detected in a substantial number of patients despite normal RV volumes and global function. MRI abnormalities within the RV outflow tract are significantly associated with the origin of tachycardia.

Asystole during dipyridamole infusion in patients without coronary artery disease or beta-blocker therapy

The authors report two patients without coronary artery disease who experienced asystole during the IV infusion of dipyridamole on routine TI-201 myocardial perfusion imaging and review the literature for possible explanations of this rare side effect. Until now, this side effect was only reported in patients with coronary artery disease or beta-blocker therapy. Yet, the cases lacked both concomitant factors and autonomic dysregulation is suggested as a cause for asystole.

Sinus node dysfunction after orthotopic heart transplantation: the Vienna experience 1987-1993

In the present study, the annual incidence of postoperative sinus node dysfunction and the type of sinus node abnormality after cardiac transplantation were followed over a 6 1/2-year period in 185 patients. Each year the sinus node function was systematically characterized by rhythm and corrected sinus node recovery time in a significant number of patients. Over the entire study period, there were 131 patients with normal sinus node function (corrected sinus node recovery time 318 +/- 55 msec) while 54 patients had latent (n = 24, sinus rhythm, corrected sinus node recovery time 8,053 +/- 2,198 msec) or manifest (n = 30, absence of sinus rhythm or pacemaker dependence) sinus node dysfunction. Twenty-nine patients had pacemaker placement. The incidence of sinus node dysfunction declined in absolute terms and when indexed by the actual number of patients transplanted per year (index 1987: 38.5; 1998: 17.6; 1989: 23.2; 1990: 29.1; 1991: 10.4; 1992: 7.5; 1993: 2.2). Among those with sinus node dysfunction, the annual percentage of patients presenting with prolonged recovery time, escape rhythm, and those reverting back to sinus rhythm until discharge did not change significantly over the study period (P = 0.22). On multivariate analysis, only the date of transplantation was significantly associated with the occurrence of postoperative sinus node deficiency (P = 0.0007) while age of recipient (P = 0.85) or donor (P = 0.96), the type of cardioplegia used (P = 0.09) and ischemic time (P = 0.09) were insignificant.(ABSTRACT TRUNCATED AT 250 WORDS)

Exercise chronotropy in patients with normal and impaired sinus node function after cardiac transplantation

The chronotropic response during graded, symptom limited exercise was investigated in 32 cardiac transplant recipients a mean of 49 +/- 18 days after transplantation. All patients had systematic evaluation of postoperative donor sinus node (SN) function and the cardioacceleratory response was compared according to the SN function. Twenty-one patients had normal postoperative SN studies (corrected SN recovery time < 520 msec, group I) while the SN function was impaired postoperatively in the remainder (n = 11, group II; corrected SN recovery time 4,149 +/- 6,283 msec in 5 patients, junctional escape rhythm in 6 patients). All patients had regained sinus rhythm at time of the exercise test. Patients in group II had lower basal sinus rates at the beginning of exercise (91.5 +/- 11 vs 101.4 +/- 7 beats/min, P < 0.02). This lower chronotropy was maintained over every incremental step (F rate between groups = 30, P = 0.0001, F rate vs workload = 15, P = 0.0001 by two-way ANOVA) and resulted in a significantly lower heart rate at individual peak exercise (108.3 +/- 20 vs 124.2 +/- 13 beats/min, P < 0.02). A total of 14/16 patients in group I but only 2/16 patients in group II accomplished a peak heart rate > or = 120 beats/min (P = 0.009). The workload achieved did not differ between the groups (107 +/- 29 vs 102 +/- 32 watts, P > 0.5). These data show a lower SN chronotropy during rest and at peak exercise in cardiac transplant recipients with postoperative SN deficiency and apparent normalization of SN function.

Management of elderly patients with the Wolff-Parkinson-White syndrome: is less aggressive treatment justified?

To study the age-related differences in Wolff-Parkinson-White syndrome an elderly group of 20 patients aged 40-65 years was compared to a younger group of 26 patients aged 18-39 years with respect to clinical profile and electrophysiological characteristics. The two groups were comparable in terms of the mechanism of reentry tachycardia, accessory pathway location, the number of patients reporting syncopal episodes, and the incidence of inducible and/or documented atrial flutter/fibrillation while only elderly patients had also atrial tachycardias. The elderly group was characterized by a higher incidence of associated organic heart disease and a significantly higher percentage of resuscitation from circulatory arrest. Cardiocirculatory arrest due to arrhythmias was the event leading to transferral to our hospital in 30% of elderly patients compared with 7.7% in the younger group. Analogous results were obtained when stratified according to the age at manifestation of tachyarrhythmias (< 30, > or = 30 years), a history of cardiopulmonary resuscitation being the only significant difference between the two groups. There was no difference in any electrophysiologic parameter between the two age groups or with respect to the age at manifestation of arrhythmias. It is concluded that elderly patients with the Wolf-Parkinson-White syndrome should be managed as aggressively as their younger counterparts. In particular, manifestation of arrhythmias due to Wolff-Parkinson-White syndrome beyond age 30 should not be regarded as a more benign variation of the syndrome. Explanations for the more frequent history of resuscitation in the elderly include the presence of organic heart disease with impairment of left or right ventricular function and differences in the management of these patients.

Relief of diastolic cardiac dysfunction after cyclosporine withdrawal in a cardiac transplant recipient

Severe heart failure developed in a 49-year-old patient 18 months after orthotopic cardiac transplantation. Acute rejection as well as other overt causes of graft failure were excluded. Haemodynamic measurements suggested severe diastolic myocardial dysfunction. Since no other causes of diastolic heart failure were identified, a potential side effect from cyclosporine was considered. Cyclosporine was therefore withdrawn and immunosuppressive treatment was switched to conventional therapy consisting of azathioprine and prednisolone. Withdrawal of cyclosporine was followed by an impressive clinical improvement and by complete haemodynamic normalization. Therefore, in cases of otherwise unexplained graft failure, a potentially reversible side effect from cyclosporine should be taken into consideration.

Normal AV node function in patients with sinus node dysfunction after cardiac transplantation

Postoperative atrioventricular nodal (AVN) function was compared in 55 patients with normal and 50 patients with impaired sinus node (SN) function after cardiac transplantation (corrected SN recovery time > 520 msec or sinus arrest +/- escape rhythm). Fifty-two patients had fixed atrial pacing at cycle lengths between 600 and 430 msec, and 53 patients at cycle lengths from 600 to 300 msec between postoperative weeks 1 to 3. Relative (stimulus-R interval; AVNRRP) and effective AVN refractory period (AVNERP) were determined in 53 patients at a cycle length of 500 msec. Only one of 105 recipients had high degree AVN conduction disturbance characterized by a Wenckebach phenomenon at cycle length < 630 msec in the first postoperative week. Three patients with normal and two patients with impaired SN function had Wenckebach cycle lengths > 430 msec while the Wenckebach cycle lengths were < or = 430 msec in the remainder (p = NS). Resting PQ interval (146 +/- 18 vs 162 +/- 32; p = 0.09), Wenckebach cycle length (350 +/- 53 vs 362 +/- 50 msec), AVNRRP (356 +/- 38 vs 367 +/- 37 msec), and AVNERP (217 +/- 48 vs 244 +/- 49 msec) did not differ significantly between patients with normal and impaired SN function. AVN conduction did not deteriorate during 318 +/- 130 days of follow-up (PQ at follow-up 154 +/- 17 and 158 +/- 22 msec, patients with normal and impaired SN function, respectively). One DDD pacemaker was placed for AVN conduction disturbance while 22 pacemakers were implanted for SN deficiency.(ABSTRACT TRUNCATED AT 250 WORDS)

Inducible atrial flutter and fibrillation after orthotopic heart transplantation

Inducible atrial flutter (two patients) and fibrillation (two patients) were observed in a series of 35 heart transplant patients who underwent evaluation of sinus node function including premature atrial stimulation. The sinus node function was entirely normal in both patients with inducible atrial flutter. In contrast it was profoundly abnormal in the patients with inducible atrial fibrillation. Atrial fibrillation was no longer inducible as the sinus node function became borderline normal. These observations suggest extensive electrical atrial abnormality, including the sinus node, in patients with atrial fibrillation, and temporary pacing should be available when considering cardioversion in patients with atrial fibrillation early after heart transplantation. Atrial flutter, in contrast, may be inducible in the absence of any sinus node abnormality and without any evidence of rejection.

Hemodynamic and hemorheologic determinants of left atrial spontaneous echo contrast and thrombus formation in patients with idiopathic dilated cardiomyopathy

The purpose of the present study was to evaluate the specific role of hemorheologic and hemodynamic parameters for spontaneous echo contrast and thrombus formation in vivo. We therefore investigated the association between the presence of left atrial spontaneous echo contrast and thrombus formation by transesophageal echocardiography and multiple clinical, hemodynamic, and hemorheologic parameters in 70 patients with idiopathic dilated cardiomyopathy. Transesophageal echocardiography showed left atrial spontaneous echo contrast and left atrial thrombi in 33% and 19% of patients, respectively. Patients with left atrial spontaneous echo contrast had a lower cardiac index (2.1 +/- 0.9 versus 2.6 +/- 0.9 L/min/m2; p < 0.02), a lower left atrial (21 +/- 8 versus 38 +/- 10 cm/sec; p < 0.001) and left atrial appendage flow velocity (17 +/- 14 versus 39 +/- 13 cm/sec; p < 0.001), a larger left atrial diameter (53 +/- 6 versus 46 +/- 10 mm; p < 0.002), and more often presented with atrial fibrillation (62% versus 32%; p < 0.02). Plasma fibrinogen concentration (4.0 +/- 1.1 versus 3.5 +/- 0.7 gm/L; p < 0.02) and plasma viscosity (1.83 +/- 0.10 versus 1.76 +/- 0.15 mPa.sec; p < 0.05) were higher in patients with spontaneous echo contrast. Multivariate analysis revealed an association between the presence of spontaneous echo contrast and left atrial flow velocity p < 0.0001) and plasma viscosity (p < 0.01). In patients with left atrial (appendage) thrombus or a history of embolism, left atrial appendage flow velocity was lower (15.0 +/- 8.2 versus 29.6 +/- 14.5 cm/sec; p < 0.005) and spontaneous echo contrast was more frequently observed (52% versus 23%; p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Different risk factor profiles in young and elderly stroke patients with special reference to cardiac disorders

The risk factors of ischemic cerebrovascular disorders in 77 young patients (< or = 40 years) were compared to those in 138 older patients (> 40 years). The risk factor profile of patients with juvenile stroke was considerably different from that of older patients. Migrainous headache and mitral valve prolapse occurred more frequently in the younger age group, whereas hypertension, diabetes mellitus, high levels of cholesterol and triglycerides were found more often in older patients with stroke. 65% of the women under the age of 40 took oral contraceptives which compares to the baseline community value of 28% of women in childbearing age in this country. Cardiac disorders such as atrial fibrillation, left ventricular hypertrophy, coronary heart disease including a history of myocardial infarction, as well as mitral valve disease were demonstrated more often in the group of elderly patients. 7 out of 77 younger patients (9.1%), and 59 out of 138 older patients (42.8%) were considered to belong to a group with "high cardiac risk for stroke". The results of this study indicate that electrocardiographic screening is of prime importance for detecting cardiac risk factors. However, echocardiographic examination often yields additional diagnostic information, particularly in younger patients. The conflicting opinions concerning the relevance of certain risk factors for ischemic stroke could partly be explained by the fact that these risk factors are distributed unevenly depending on age.

The electrophysiology of cardiac allograft rejection: independent effects of rejection and perioperative ischemia on the sinus node recovery phenomenon after cardiac transplantation

We characterized the effect of cardiac allograft rejection on the sinus node (SN) recovery response from overdrive suppression. A total of 54 corresponding data sets (SN recovery time [SNRT]/endomyocardial biopsy [EMB]) was available in 24 transplant recipients with normal SNRT. Data were pooled in the rejection vs the no-rejection group (n = 16 vs n = 38, respectively). During cardiac rejection (defined as a 7-day period starting 3 days prior to and lasting until 3 days after the EMB) the SNRT curves were moderately, but significantly shifted towards higher values (F = 13.4, p = .0003). All changes occurred within accepted normal limits for the SNRT. Multivariate analysis indicated independent effects of donor heart ischemic time (p = .0005) on SNRT in addition to that of rejection. After accounting for that influence of ischemic time respective F values regarding the influence of rejection on the SNRT excursions were 10.8 (ischemic time < 100 min, p = .0014) and 4.36 (ischemic time > or = 100 min, p = .039). This study shows that cardiac allograft rejection significantly delays the SN recovery response from overdrive suppression. These changes, however, are subtle and, hence, are an unlikely explanation for the often grossly abnormal postoperative SN function.

Long-term intrinsic pacemaker function in patients paced for sinus node deficiency after cardiac transplantation

Fifteen cardiac transplant recipients requiring permanent pacing (AAI, n = 9; VVI, n = 6; rate responsive devices, n = 11) for postoperative sinus node (SN) insufficiency underwent evaluation of long-term SN function 240 to 1,461 days after transplantation. The intrinsic rhythm at the time of discharge was sinus in 7 patients; junctional escape in 6 patients; and pacemaker dependent in 2 patients. At follow-up, 5 patients had regained regular sinus rhythm, accounting for a total of 11 patients in sinus rhythm while 4 patients were in junctional bradycardia. The SN recovery time as determined by the permanent pacemaker was normal (< 1,500 msec) in only 1/8 patients in whom it was determined, although 4 of these 8 patients were temporarily overriding the pacemaker during ambulatory monitoring. Patients with pathological SN recovery times included 3 patients with late return of sinus rhythm and 4 patients who had recovered normal sinus rhythm before their discharge from the hospital. Three patients developed late symptoms despite apparent early normalization and underwent delayed pacemaker implantations on postoperative days 35, 52, and 225, respectively. We conclude that, in patients requiring pacemaker implantation after cardiac transplantation, normalization of SN function cannot be inferred from just return of sinus rhythm, regardless of whether it occurs early or late. These findings may have implications when a pacemaker exchange or explantation is being considered.

Prognostic value of heart rate variability in patients awaiting cardiac transplantation

Time and frequency domain parameters of heart rate variability (HRV) were determined in patients with severe endstage heart failure awaiting cardiac transplantation (HTX). These parameters were then correlated with mortality to investigate the performance of HRV in discriminating between groups with high and low risk of death. The standard deviation of five consecutive RR intervals (SDANN) was found to be the parameter with the greatest sensitivity (90%) and specificity (91%). Patients with SDANN values of < 55 msec had a twenty-fold increased risk of death (90% confidence limits: 4-118, P < 0.001). The results furthermore suggest that measurements of HRV are superior to other prognostic markers such as left ventricular ejection fraction, pulmonary artery wedge pressure, cardiac index, and serum sodium levels. We conclude that HRV is a powerful, noninvasive tool to assess the risk of death in candidates for HTX. HRV measurements can therefore be used as a supplement to other markers of risk to determine the optimal therapeutic strategy in patients with severe congestive heart failure.

Drug-testing in patients with pulmonary hypertension of unknown cause

The acute haemodynamic effects of seven different drugs were serially evaluated in eight patients suffering from pulmonary hypertension of unknown cause. The following drugs were tested in randomized order: nifedipine, amrinone, isoproterenol, captopril, prostacyclin, dihydralazine and nitroglycerin. Only a reduction in pulmonary vascular resistance (PVR) of more than 30% of baseline was considered a satisfactory response. Overall, the decrease in PVR ranged from 9 +/- 12% (nitroglycerin) to 38 +/- 23% (prostacyclin). However, marked inter- and intra-individual variability in the efficacy of all drugs was observed, making cross reactivity totally unpredictable. The number of responders for each drug varied between five (prostacyclin) and zero (dihydralazine, nitroglycerin). Conversely, a maximum of three drugs was capable of eliciting a response in an individual patient, with only two out of eight patients being total non-responders. A reduction in PVR of more than 30% (n = 16) was associated with a significant decrease in mean pulmonary artery pressure (49.1 +/- 8.2 versus 39.4 +/- 6.4 mmHg) and a significant increase in cardiac index (2.5 +/- 0.6 versus 3.4 +/- 0.8l.min-1.m-2). Overall, none of the drugs tested proved to be clearly superior. However, because of marked inter- and intra-individual variability, the therapeutic approach must be based on trial and error and the evaluation of all drugs is indicated if one fails.

Significance of left-sided heart disease for the detection of patent foramen ovale by transesophageal contrast echocardiography

Detection of patent foramen ovale by contrast echocardiography is based on transient inversion (right atrial pressure higher than left atrial pressure) of the interatrial pressure gradient. Therefore, the presence of left-sided heart disease with potential elevation of left atrial pressure might obscure the diagnosis of patent foramen ovale. Accordingly, 150 patients (88 men, 62 women; mean age 51.7 +/- 15.2 years) were evaluated for a patent foramen ovale by transesophageal contrast echocardiography. Additionally, atrial septal motion during normal respiration and during the Valsalva maneuver was analyzed. Patency of the foramen ovale was observed in 20 (27%) of 74 patients without left-sided heart disease and with previous arterial embolism, in none (0%) of 25 patients with left-sided heart disease and embolism, in 7 (39%) of 18 patients without left-sided heart disease and without embolism and in 3 (9%) of 33 patients with left-sided heart disease and without embolism. The detection rate of patent foramen ovale was lower in patients with than without left-sided heart disease (5% vs. 29%, p = 0.0007) but was similar in patients with and without embolism (20% vs. 19.5%, p = NS). Abnormal atrial septal motion was more frequently observed in patients with left-sided heart disease (p = 0.0003) and was inversely correlated to detection of patent foramen ovale (p = 0.0003). Multivariate analysis revealed an independent association between the absence of left-sided heart disease and the detection of patent foramen ovale (p = 0.0003). These data suggest that in patients with left-sided heart disease, patency of the foramen ovale may be missed even by transesophageal contrast echocardiography.

Postoperative sinus node dysfunction in the transplanted heart. Impaired automaticity but normal refractoriness

We describe the use of the extrastimulus technique to define the range of sinus node (SN) effective refractoriness (SNERP) in the denervated transplanted human heart. SNERP could be successfully determined in 18 of 28 patients corresponding to 25 of 43 SN studies and ranged from 210 to 360 ms at a basic pacing cycle length of 500 ms (95 percent confidence limits: 252.5 to 296.2 ms), which is shorter than reported in the innervated native heart. Sixteen data sets in 12 patients showed normal SN function and nine sets of measurements in seven patients showed abnormal SN function (corrected SN recovery time greater than 520 ms). While recovery time was profoundly abnormal (279.7 +/- 94 vs 7,284.8 +/- 10,454, p less than 0.001), the SNERP did not differ significantly between the groups (274.3 +/- 40 vs 286 +/- 42 ms at 500 ms, p = 0.5) and was normal at a range of 220 to 340 ms even in those patients with grossly impaired SN recovery (SNERP in patients with normal SN function: 210 to 360 ms at 500 ms). This study demonstrates that SN refractoriness in the transplanted human heart is shorter than previously reported in innervated controls and suggests that posttransplantation SN dysfunction is characterized by impaired automaticity rather than impaired refractoriness.

Improvement in left ventricular systolic function after successful radiofrequency His bundle ablation for drug refractory, chronic atrial fibrillation and recurrent atrial flutter

Incessant supraventricular tachyarrhythmia may lead to a reversible impairment of left ventricular (LV) function. This issue was investigated in 10 patients (aged 64 +/- 13 years) who underwent radiofrequency His bundle ablation for control of drug refractory, chronic atrial fibrillation (n = 9) and recurrent atrial flutter (n = 1). LV function was assessed by 2-dimensional guided M-mode echocardiography within 24 hours (baseline) and 49 +/- 18 days (follow-up) after successful ablation, both during VVI pacing at 70 beats/min. Fractional shortening increased from 28 +/- 9% at baseline to 35 +/- 8% at follow-up (p = 0.006). This increase in fractional shortening was due to a significant reduction of end-systolic diameter from 41 +/- 10 to 36 +/- 10 mm (p = 0.02), whereas there was no appreciable change in end-diastolic diameter (56 +/- 7 to 55 +/- 10 mm; p = 0.5). These changes were substantially greater in patients with baseline impairment of LV function (fractional shortening less than 27%). Fractional shortening increased by 12% (p = 0.14) in patients with normal LV function (n = 5) and by 44% (p = 0.02) in those with impaired LV function at baseline (n = 5). The greater increase in fractional shortening in patients with preexisting LV impairment was due to a more pronounced decline in end-systolic dimensions (-11.9%; p = 0.08) compared with that of patients with normal LV function at baseline (-9.21%; p = 0.2). End-diastolic diameter showed no significant change in either group (-3.53% [p = 0.8] and -0.58% [p = 0.4]).(ABSTRACT TRUNCATED AT 250 WORDS)

Distribution of ischemic cerebrovascular events in cardiac embolism

Distribution and number of ischemic cerebrovascular events were studied in 57 patients who suffered from heart disorders with proven or highly probable source of cardiac embolism and compared to 39 patients with ulcerations of the craniocervical vessels. Patients with coexisting lesions were excluded from the present study. Out of the 57 patients with cardiac disorders, a single episode of cerebral embolism occurred in 33 patients. Of the 24 patients with recurrent ischemic episodes, different vascular territories were involved in only six cases. There was no evidence of a distinct distribution of vascular territories involved in cerebral embolism. The left middle cerebral artery was affected in 42.9%, the right middle cerebral artery in 23.8%, the vertebrobasilar territory in 19%, and the ophthalmic arteries in 14.2%. Statistical analysis revealed no significant differences in lesion localization between the group with a cardiac source of embolism and the group with ulcerations of the craniocervical vessels. There was a high frequency of patients with recurrent cardiogenic emboli in the ophthalmic (6 of 9 patients) as well as in the vertebrobasilar (6 of 12 patients) circulation who experienced a delayed initiation of cardiac assessment. The possibility of cardiac embolism should be considered in any patient with cerebral ischemia, independently of the vascular territory affected.

Demographic and perioperative factors associated with initial and prolonged sinus node dysfunction after orthotopic heart transplantation. The impact of ischemic time

The etiology of sinus node (SN) dysfunction after orthotopic heart transplantation as assessed by the origin of rhythm, heart rate (HR), and, provided the origin of rhythm was sinus, by corrected sinus node recovery time (CSNRT) was studied in 50 patients. The possible influences on postoperative donor SN function of donor age, recipient age, underlying pretransplant heart disease, pretransplant amiodarone (AMIO) treatment, date of surgery, ischemic time, surgical technique of atrial incision, the use of different cardioplegic solutions during the study period, and rejection were evaluated. The results thus obtained indicate that SN dysfunction is common after cardiac transplantation and pinpoint to a different etiology of transient (restoration of normal SN function within 4 postoperative weeks) and persistent (SN function still impaired at 3 months) SN dysfunction. Of the several demographic and perioperative variables evaluated, only ischemic time had an influence on postoperative SN function in that ischemic times were significantly longer in patients with impaired SN function when compared with patients exhibiting normal SN function (148 +/- 39 min vs. 110.5 +/- 36 min, respectively, P = 0.001). Further stratification according to the duration of SN dysfunction revealed significantly longer ischemic times in patients with transiently impaired SN function only (156.3 +/- 35 min vs. 110.5 +/- 36 min, P = 0.0026). No relation to persistent SN dysfunction of ischemic time (130.5 +/- 36 min vs. 110.5 +/- 36 min, P = ns) or any other factor investigated was found.

Electrophysiologic testing after aortic valve replacement in two patients with aortic stenosis and preoperative ventricular fibrillation

In two patients with severe aortic stenosis successful resuscitation from ventricular fibrillation was documented by Holter recording/ECG monitoring. After aortic valve replacement programmed ventricular stimulation was performed in both patients, but ventricular tachycardia/ventricular fibrillation was not inducible. The patients were left without antiarrhythmic therapy and have been free from cardiac events for 18 and 20 months, respectively. The prognostic value of postoperative electrophysiologic testing after aortic valve replacement in patients with severe aortic stenosis and preoperative resuscitation is discussed.

[The effect of concomitant aortic valve insufficiency on the values of Doppler sonographic gradient determination in patients with aortic stenosis]

We examined the influence of concomitant significant aortic incompetence (AI) on Doppler-gradient measurements in valvular aortic stenosis (AS) by comparing catheter and Doppler gradients of 51 patients with isolated AS and of 24 patients with additional AI. In patients with additional AI there was a significantly greater overestimation of the peak-to-peak gradient by the maximal instantaneous Doppler gradient (AS + AI: overestimation 31.0 +/- 17.6 mm Hg, AS: overestimation 10.5 +/- 20.2 mm Hg; p less than 0.01) and also by the maximal instantaneous catheter gradient (AS + AI: overestimation 32.8 +/- 11.8 mm Hg, AS: overestimation 20.4 +/- 14.0 mm Hg; p less than 0.01). Comparison of the respective catheter-derived and Doppler-sonographically measured instantaneous and mean gradients showed no differences between the two patient subgroups. Higher instantaneous gradients in patients with additional AI are mainly explained by the lower end-diastolic aortic pressure. However, Doppler-sonographic overestimation of the severity of stenosis in patients with combined AS + AI, due to the sole measurement of the instantaneous gradient in clinical practice, should be of limited importance because in these patients significant AI already sufficiently indicates aortic valve replacement.

Day to day reproducibility of Doppler sonographic measurements in patients with valvular aortic stenosis

High reproducibility of Doppler gradient measurements is necessary for both the reliable noninvasive assessment of the severity of aortic stenosis and for repeated follow-up examinations in individual patients. We therefore studied day to day reproducibility of Doppler sonographically measured peak pressure drops in 46 patients with valvular aortic stenosis. Clinically stable patients were examined twice within 29 +/- 18.2 days by the same examiner. Peak pressure drop (PPD) and peak flow velocity differed between the two examinations by 8.6 +/- 7.0 (range 0-29) mmHg and by 0.25 +/- 0.18 (range 0-0.7) m/s, respectively. Reproducibility was comparable in patients with excellent, good, and moderate quality examinations, but was lower in the 6 patients with poor quality examination. Variability of PPD, but not of peak flow velocity was higher (p less than 0.05) in patients with severe (PPD greater than 60 mmHg) stenosis. Reproducibility was comparable in patients with or without concomitant aortic incompetence and in patients with normal or reduced left ventricular function. Similar reproducibility was obtained in patients with heart rate changes below or above 10 beats/min between the two examinations. It is concluded that good reproducibility of Doppler measurements in patients with aortic stenosis allows reliable noninvasive assessment of the severity of the stenosis. In follow-up studies of patients with mild to moderate aortic stenosis increases in peak flow velocity in excess of 15% (mean day to day variability +2 SD) are highly indicative of the true progress of the stenosis.

Evidence for an increased generation of prostacyclin in the microvasculature and an impairment of the platelet alpha-granule release in chronic renal failure

The formation of prostacyclin (PGI2) and thromboxane A2 and the release of beta-thromboglobulin (beta-TG) at the site of platelet-vessel wall interaction, i.e. in blood emerging from a standardized injury of the microvasculature made to determine bleeding time, was studied in patients with end-stage chronic renal failure undergoing regular haemodialysis and in normal subjects. In the uraemic patients, levels of 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha) were 1.3-fold to 6.3-fold higher than the corresponding values in the control subjects indicating an increased PGI2 formation in chronic uraemia. Formation of thromboxane B2 (TxB2) at the site of plug formation in vivo and during whole blood clotting in vitro was similar in the uraemic subjects and in the normals excluding a major defect in platelet prostaglandin metabolism in chronic renal failure. Significantly smaller amounts of beta-TG were found in blood obtained from the site of vascular injury as well as after in vitro blood clotting in patients with chronic renal failure indicating an impairment of the alpha-granule release in chronic uraemia. We therefore conclude that the haemorrhagic diathesis commonly seen in patients with chronic renal failure is--at least partially--due to an acquired defect of the platelet alpha-granule release and an increased generation of PGI2 in the microvasculature.

[Electrophysiologic study in patients with syncope of unknown cause]

Electrophysiologic studies were performed in 51 patients with syncopes of unexplained origin. 25 patients (49%) had organic heart disease. Electrophysiologic testing included determination of corrected sinus node recovery time, AV-nodal effective refractory period, AH- and HV-intervals, and AV-nodal Wenckebach rate. During programmed right ventricular stimulation, 1-3 premature stimuli were used. 26 patients (53%) had an abnormal outcome that strongly suggested an arrhythmogenic cause of the reported syncopes. In ten patients (20%), corrected sinus node recovery time was prolonged; AV-nodal conduction disturbance was manifest in two patients (4%); reversibility with atropine was shown in one patient. Six patients (12%) had an infrahisian conduction delay with an HV-interval longer than 70 ms. Eight patients (15.6%) had either symptomatic ventricular tachycardias (n = 4), AV-nodal reentry tachycardias (n = 2), or inducible symptomatic rapid atrial fibrillation (n = 2). In one additional patient, ventricular tachycardias could not be reinitiated after ending tricyclic antidepressant drug medication. The diagnostic yield of the electrophysiologic study was not influenced by the presence of organic heart disease. Patients with prolonged corrected sinus node recovery time, prolonged HV-interval, and irreversible AV-conduction delay underwent pacemaker implantation (n = 17). Patients with rapid response to programmed stimulation received antiarrhythmic medication, the efficacy of which was assessed by serial electrophysiologic testing until non-inducibility was obtained. The mean follow-up period was 11 months (1-31 months). Overall 2-year mortality was 17%. In 4/5 patients, death was unrelated to the cause of syncope.(ABSTRACT TRUNCATED AT 250 WORDS)

Human blood basophils display a unique phenotype including activation linked membrane structures

To evaluate the membrane marker profile of human basophils a panel of well-established monoclonal antibodies (MoAbs, n = 60) was used for a combined toluidine/immunofluorescence staining procedure. Myeloid-associated MoAbs (particularly MoAbs against the LFA-1 family (CD11, CDw18), MoAbs directed against lactosylceramide (CDw17), anti-glycoprotein (gp) 150 MoAbs MCS 2 and MY 7 (CDw13), anti-gp 67 MoAb MY 9, anti Fc gamma-receptor (mol wt 40 kd) MoAb CIKM5, anti-CR 1 MoAb E 11, and the antiglycolipid MoAb VIM-2) were reactive with basophils, indicating a close relationship to other mature myeloid cells. Under normal conditions, basophils surprisingly express at least three activation-linked structures not detectable on mature neutrophils, ie, the p45 structure defined by MoAbs OKT-10 and VIP-2b, the p24 structure identified by the CD9 MoAb BA-2, and the receptor for interleukin 2 (IL 2) recognized by three different MoAbs (anti-TAC, IL2RI, anti-IL 2). Moreover, under short-term culture conditions basophils both in mononuclear cell (MNC) suspension and as purified fractions display the HLA-DR and T4 antigens. The neutrophilic/eosinophilic structure 3-fucosyl-N-acetyllactosamine is expressed on basophils only after neuraminidase treatment. Basophils were not stained at all by CD 16 MoAbs directed against the Fc gamma-receptor (mol wt 50 to 70 kd) of neutrophils, by the MoAb 63D3 (CDw12) recognizing the monocyte/granulocyte-associated p 200 antigen, and by the CDw 14 antibodies (VIM-13, Mo 2) defining the monocyte-specific structure p 55. Enriched basophils freshly obtained from chronic granulocytic leukemia (CGL) patients yielded identical results in FACS analyses. In summary, these data indicate that basophils generate a unique combination of surface determinants and possibly represent an activated cell population.

[Doppler echocardiographic determination of aortic valve gradients]

Doppler-echocardiography is the most important non invasive method for the assessment of the severity of aortic stenosis. After measuring the maximal transstenotic flow velocity (= Vmax) the maximal pressure drop between left ventricle and aorta (= maximal instantaneous gradient) can bei calculated according to a simple formula. The accurate determination of Vmax may be difficult and time consuming, however, and when interpreting the Doppler-data it is important to realize that there is always a systematic numerical difference between the instantaneous gradient and those gradients which one usually measures at catheterization (peak to peak and mean gradient respectively). In mixed aortic valve disease the aortic insufficiency will distort the relationship between the various gradients still further. Despite these problems Doppler-echocardiography is extraordinarily useful in quantitating aortic stenosis and obviates the need for catheterization in most patients.

[Sudden cardiac death during long-term ECG monitoring of a patient with aortic stenosis]

Sudden cardiac death was documented on a Holter-monitor ECG in a 71-year-old man with known, but unoperated, calcific aortic stenosis (peak transvalvar gradient of 90 mm Hg). The tracing showed the development of a, presumably stress-induced, sinus tachycardia with broad QRSs and rapid transition to ventricular fibrillation. This rarely documented example of cardiac death in a patient with aortic stenosis during long-term ECG monitoring is of special interest because the patient had neither an inverse therapy effect nor impaired left-ventricular function.

[Oral anticoagulant therapy--renaissance of an old therapy?]

Although the antithrombotic potential of oral anticoagulants is undisputed, bleeding complications constitute a serious problem. One of the main causes for these complications has been a lack of standardization of the prothrombin time. The introduction of the International Normalized Ratio (INR) has led to a better standardization of prothrombin time. Thus, the same level of anticoagulation can be reached using different reagents and therefore over- and undercoagulation can be avoided. Furthermore, the benefit/risk ratio can be improved by adapting the intensity of anticoagulation to the indication. The following clinical conditions are established indications for treatment with oral anticoagulants: Prevention of cardiac emboli in acute anterior myocardial infarction with atrial thrombus, in patients with atrial fibrillation with or without mitral valve disease, in patients with prosthetic heart valves and in patients with dilated cardiomyopathy. Furthermore, oral anticoagulants should be given to patients after femoropopliteal bypass. A relatively mild oral anticoagulant treatment (INR 2-3) is sufficient to prevent recurrences of venous thrombosis and pulmonary emboli. The duration of treatment in patients with venous thromboembolism depends on some clinical features and the results of clotting tests which indicate an increased tendency to thrombosis.

[Hemofiltration for the reduction of lung fluid in ARDS?]

Hemofiltration has been advocated for reduction of extravascular lung water (EVLW) in both clinical and experimental ARDS. The influence of hemofiltration on EVLW was studied retrospectively in 10 patients with this syndrome. After 2 to 38 hours' hemofiltration net fluid balance was -3640 +/- 3609 ml. EVLW remained almost unchanged (from 17.6 +/- 5.4 before to 15.6 +/- 4.1 ml/kg after hemofiltration). In 4 patients a reduction of over 15% in EVLW was achieved, whereas in the remaining 6 patients EVLW changed within a range of +/- 10%. However, hemofiltration caused a decrease in cardiac output and oxygen delivery, thereby adversely affecting its benefits on EVLW and gas exchange. In ARDS hemofiltration should be performed under careful hemodynamic monitoring and only in some of the patients an immediate reduction in EVLW can be achieved.

Thromboembolism in patients with prosthetic heart valves. An adequately controlled intense anticoagulant therapy and its influence on the occurrence of thromboembolism in relation to valve type

This study was designed to evaluate the efficacy of carefully controlled treatment with oral anticoagulants in patients with different mechanical heart valve prostheses. One hundred eighty-one patients with various types of prosthetic valves (mitral 89, aortic 87, combined 5) received oral anticoagulation aiming at Thrombotest (TT) values between 5% and 12%. Median follow-up was 46 months; 80.8% of all TT determinations were below 12%. The thromboembolic rate was 0.25%/year in patients with aortic valve replacement (AVR) and 4.87%/year in patients with mitral valve replacement (MVR). There was a strikingly lower incidence of thromboembolism with newer types of valves (Björk-Shiley convex-concave) in the mitral position under exactly the same intensity and stability of anticoagulant treatment. Clinically overt valve occlusion could be almost completely prevented (0.12%/year) in prostheses at both sites. Severe hemorrhage occurred at a rate of 1.71%/year and fatal bleeding at a rate of 0.37%/year. Our results indicate that carefully controlled anticoagulation is effective in the reduction of thromboembolic complications at a reasonable risk of bleeding.

Hemodynamic, pulmonary, and renal reactions to inadvertent transfusion of outdated blood

A patient who received an erroneous transfusion of outdated and partly homogenized blood is reported. Although marked hemoglobinemia was present, only transient hemodynamic, pulmonary, and renal alterations were observed. Massive embolism of microaggregates and norepinephrine release might explain our findings. Dopamine (3 micrograms/kg . min) might have beneficial effects on renal function in this pseudohemolytic transfusion reaction.

Prevention of arterial and pulmonary embolism by oral anticoagulants in patients with dilated cardiomyopathy

The incidence of arterial embolism (AE) and pulmonary embolism (PE) during treatment with oral anticoagulants (OA) or without OA therapy was studied in 38 patients with dilated cardiomyopathy (DCMP). AE/PE occurred in 17 patients (44.7%) before initiation of OA treatment. The severity of DCMP was a risk factor for AE/PE, but not the presence of atrial fibrillation or intracardial thrombi. No AE/PE episodes occurred during the period of OA therapy. No major bleeding complications were seen, probably due to the moderate intensity of OA therapy (therapeutic range 5-15% Thrombotest [TT], 2.1-4.8 International Normalized Ratio [INR], median TT value 11%, median INR 2.6). Recurrence of AE was observed in 4 of 5 patients in whom treatment with OA had been discontinued.

Prevention of Arterial and Pulmonary Embolism by Oral Anticoagulants in Patients with Dilated Cardiomyopathy

The incidence of arterial embolism (AE) and pulmonary embolism (PE) during treatment with oral anticoagulants (OA) or without OA therapy was studied in 38 patients with dilated cardiomyopathy (DCMP). AE/PE occurred in 17 patients (44.7%) before initiation of OA treatment. The severity of DCMP was a risk factor for AE/PE, but not the presence of atrial fibrillation or intracardial thrombi. No AE/PE episodes occurred during the period of OA therapy. No major bleeding complications were seen, probably due to the moderate intensity of OA therapy (therapeutic range 5-15% Thrombotest® [TT], 2.1-4.8 International Normalized Ratio [INR], median TT value 11%, median INR 2.6). Recurrence of AE was observed in 4 of 5 patients in whom treatment with OA had been discontinued.

Efficacy of the M-2 protocol in previously untreated patients with advanced multiple myeloma

37 consecutive, previously untreated patients with advanced multiple myeloma (16 patients Stage II, 21 patients Stage III) were treated with a five drug regimen consisting of carmustine, melphalan, vincristine, cyclophosphamide and prednisolone (M-2-protocol) in a prospective manner. Remission was achieved in 24 patients (65%). The median time to remission was 10 weeks, the median duration of remission 15,3 months. Median survival time from the onset of treatment was 24 months for all patients. Responding patients have a projected 65% three year survival. Median survival in non-responders was 10 months. 8 patients died during the first year of treatment. These results do not confirm the favourable results with this drug combination obtained in a previous trial. The discrepancy may be explained by a higher proportion of poor risk patients in the present study.

Impaired fibrinolytic capacity predisposes for recurrence of venous thrombosis

The fibrinolytic capacity of 121 patients with a history of venous thrombosis and/or pulmonary embolism was studied by venous occlusion technique, at earliest 3 months after the last thromboembolic episode. After discontinuation of oral anticoagulation treatment the clinical course of the patients was followed and new thromboembolic episodes were noted. During the observation period of 56 +/- 18.8 months 45 of 121 patients experienced recurrence of thrombosis. The recurrence-rate was significantly lower in patients with a post-occlusion ELT shorter than 60 min (4.8%/year) than in patients with an ELT longer than 60 min (10.3%/year). It is concluded that the fibrinolytic capacity is a useful parameter for determining the risk of recurrence in patients with venous thrombosis.

Haemophilus parainfluenzae endocarditis on tricuspid valve

After an episode of intermittent fever which lasted 45 days, endocarditis of the tricuspid valve was diagnosed using M-mode echocardiography in a 17-year-old female patient who had no history of drug abuse. After unsuccessful therapy with ampicillin, tetracycline and aminoglycosides, clinical improvement was achieved by treatment with temocillin.

[Poisoning with andromedotoxin-containing honey]

Two patients poisoned by andromedotoxin-containing honey were treated in Austrian hospitals in 1981 and 1982. The toxin-containing honey had in both cases been obtained in the coastal mediterranean part of Turkey. Both patients had severe arterial hypotension, bradycardic arrhythmias, syncope and CNS symptoms. Symptomatic treatment was fully successful in both patients within 24 hours.

[Clinical aspects and therapy of acute poisoning by the drug combination melitracen-flupenthixol (Deanxit)]

From 1975 to 1982, the Austrian Poison Information Centre gave medical advice in forty cases of acute melitracenee-flupenthixol poisoning. The case reports were reviewed and analysed in retrospect. 13 patients who either had ingested less than 20 pills (n = 5) or who underwent early gastric lavage (n = 8) showed no symptoms. In 19 patients who had swallowed 20 to 60 (n = 11), 60 to 100 (n = 3) pills respectively, or an unknown dose (n = 5) atropine like symptoms predominated. Five patients developed atropine like and extrapyramidal symptoms. The number of pills taken by these patients ranged from 20 to 60 (n = 4) and in one up to 100. Extrapyramidal reactions were encountered as predominant symptoms in three patients one of which had taken 20, the other 60 and the third an unknown number of pills. Additionally, five patients were unconscious. 21 patients developed ECG changes, 19 of which showing sinus tachycardia. The remaining two patients who had ingested 600 to 1000 mg melitracen atrial premature beats or T-wave inversions were observed. All 40 patients recovered.

[Poisoning with clonidin hydrochloride in children and adults]

In this study clinical findings are presented of 31 patients with clonidinee intoxication and the therapeutic measures taken in these cases are discussed. In toddlers poisoning is seen after ingestion of a single tablet of 150 micrograms clonidine, whilst in adults poisoning may occur already at a dosage just exceeding the therapeutic limit, which is subject to wide individual variation (1 to 3 tablets). Primary elimination procedures must be instituted at these dosages, but, because of the rapid absorption of clonidine, gastric lavage and induced emesis provide no benefit to patients with complete symptomatology or those who took the overdose several hours before. Chlorpromazine-like effects, hypotension and bradycardia proved to be the outstanding features. Respiratory depression, disturbances of myocardial conduction or hypertension were less frequent. Symptoms lasted for a mean of 15.5 +/- 8.6 hours, with a range of 4 to 36 hours. Fluid therapy and, as necessary, dopamine for hypotension, phentolamine for hypertension and atropine for bradycardia caused prompt improvement in addition to essential measures such as meticulous control of respiratory function, body temperature and of ECG changes. There was no need to implement the central clonidine antagonist, tolazoline in any of these cases.