Arrhythmias In Hemodialysis Patients Research Articles

Effects of dialysate potassium concentration of 3.0mEq/l with sodium zirconium cyclosilicate on dialysis-free days versus dialysate potassium concentration of 2.0mEq/l alone on rates of cardiac arrhythmias in hemodialysis patients with hyperkalemia

The optimal approach towards managing serum potassium and hemodialysate potassium concentrations is uncertain. To study this, adults receiving hemodialysis for three months or more with hyperkalemia (pre-dialysis serum potassium (sK+) 5.1-6.5 mEq/l) had cardiac monitors implanted and were randomized to either eight weeks of 2.0 potassium/2.5 calcium mEq/l dialysate without sodium zirconium cyclosilicate (SZC) (2.0 potassium/noSZC) or 3.0 potassium/2.5 calcium mEq/l dialysate combined with SZC (3.0 potassium/SZC) on non-dialysis days to maintain pre-dialysis sK+ 4.0-5.5 mEq/l, followed by treatment crossover for another eight weeks. The primary outcome was the rate of adjudicated atrial fibrillation (AF) episodes of 2 minutes or more duration. Secondary outcomes included clinically significant arrhythmias (bradycardia, ventricular tachycardia, and/or asystole) and the proportion of sK+ measurements within an optimal window of 4.0-5.5 mEq/l. Among 88 participants (mean age: 57.1 years; 51% male; mean pre-dialysis sK+: 5.5 mmol/l) with 25.5 person-years of follow-up, 296 AF episodes were detected in nine patients. The unadjusted AF rate was lower with 3.0 potassium/SZC versus 2.0 potassium/noSZC; 9.7 vs. 13.4/person-year (modeled rate ratio 0.52; 95% confidence interval: 0.41; 0.65). Clinically significant arrhythmias were reduced with 3.0 potassium/SZC vs. 2.0 potassium/noSZC 6.8 vs. 10.2/person-year modeled rate ratio 0.47: 0.38;0.58). Fewer sK+ measurements outside the optimal window occurred with 3.0 potassium/SZC (modeled odds ratio: 0.27:0.12, 0.35). Hypokalemia was less frequent (33 vs. 58 patients) with 3.0 potassium/SZC compared with 2.0 potassium/noSZC. Thus, in patients with hyperkalemia on maintenance hemodialysis, a combination of potassium 3.0 mEq/l and SZC on non-hemodialysis days reduced the rates of AF, other clinically significant arrhythmias, and post-dialysis hypokalemia compared with potassium 2.0/noSZC.

Spironolactone and Cardiac Arrhythmias in Hemodialysis Patients: Helpful or Harmful?

Spironolactone and Cardiac Arrhythmias in Hemodialysis Patients: Helpful or Harmful?

Effects of Spironolactone on Arrhythmias in Hemodialysis Patients: Secondary Results of the SPin-D Randomized Controlled Trial.

Background Patients receiving maintenance hemodialysis (HD) have a high incidence of cardiovascular events, including arrhythmia and sudden death. Spironolactone reduces the risk of cardiovascular events and sudden death in patients with heart failure, but the effects of spironolactone on arrhythmic events in patients treated with maintenance HD are unclear. Methods The Safety and Cardiovascular Efficacy of Spironolactone in Dialysis-Dependent ESRD (SPin-D) trial, was a 36-week randomized, placebo-controlled, double-blind trial comparing 3 different doses of spironolactone with placebo in maintenance HD patients. We performed a post-hoc analysis in a subset (n=57) who underwent extended electrocardiographic monitoring using a wearable device at baseline and follow-up. Generalized estimating equations models were fit to determine the associations of spironolactone (individual doses and combined) versus placebo on the incidence rate of predefined categories of arrhythmic events. Results The average age of participants was 55 ±12 years; 61% were male; and 77% were Black. The overall proportion of patients with at least one arrhythmia event was 43% (15/35) at baseline and 81% (43/53) at the end of follow-up. At the end of follow-up, the rate of bradycardic events or conduction blocks was higher in the combined spironolactone group, compared with placebo, (82.4 versus 38.7 events/100 patient days; P<0.001). Similar findings were noted in adjusted models, but did not meet statistical significance (adjusted rate ratio of 2.04; 95%CI 0.83 - 5.05). Conclusions In a 36-week trial of patients receiving maintenance hemodialysis, a higher frequency of bradycardia and conduction blocks was observed among those treated with spironolactone treatment compared with placebo. Larger studies are required to investigate the longer-term effects of spironolactone on cardiac conduction in patients receiving hemodialysis.

Presence of Fragmented QRS may be Associated with Ventricular Arrhythmias in Hemodialysis Patients

Presence of Fragmented QRS may be Associated with Ventricular Arrhythmias in Hemodialysis Patients

A Systematic Review of the Incidence of Arrhythmias in Hemodialysis Patients Undergoing Long-Term Monitoring With Implantable Loop Recorders

IntroductionEstablishing the frequency and nature of arrhythmias in hemodialysis (HD) is an important step in improving outcomes of these patients. We undertook this systematic review and meta-analysis to characterize arrhythmia frequency in maintenance HD patients.MethodsWe identified studies on arrhythmias in adult patients on maintenance HD detected via implantable loop recorders (ILRs). Studies included were in English and reported ILR-detected arrhythmia incidence in HD patients. Data were extracted by one author using electronic spreadsheets and verified by a second author. Random effects models were used for pooled inferences. The I2 statistic was used to quantify heterogeneity.ResultsFive studies qualified for inclusion (317 patients). The overall estimates for the annualized rate of death and sudden cardiac death (SCD) was 0.14 (95% confidence interval [CI]: 0.11–0.18) and 0.06 (95% CI: 0.03–0.10), respectively. Across all 5 studies, the combined annualized rate of patients experiencing at least 1 bradycardia/asystole event was 0.19 (95% CI: 0.11–0.33) but heterogeneity was high (I2 = 79.8%). The average annualized rate of sustained ventricular tachycardia (VT) or ventricular fibrillation (VF) episodes (0.02, 95% CI: 0.01–0.05) was significantly lower (P < 0.001) than the rate of bradycardia/asystole reported in the same patients. Incidence of atrial fibrillation (AF) varied significantly across the studies (from 0.07 to 0.83 patients per year) reflecting variable definitions (new-onset vs. total number of episodes).ConclusionThe incidence of arrhythmias among chronic HD patients is high, with bradycardia/asystole occurring more frequently than ventricular arrhythmias. Additional studies to refine estimates particularly of AF are needed.

Electrocardiographic Changes and Cardiac Arrhythmias in Hemodialysis Patients with End-Stage Renal Disease, at AL-Hussein Teaching Hospital

Background: Cardiovascular disease is the leading cause of mortality among patients on dialysis. Whenconsidering all causes of death, about 30% are classified as cardiac arrest, death of unknown cause or cardiacarrhythmia. The increasing time of ventricular depolarization and repolarization, measured non-invasivelyby measuring the QT interval on the electrocardiogram at rest, has emerged as a predictor of complexventricular arrhythmias, a major cause of sudden cardiac death.Objective: To evaluate electrocardiographic abnormalities in patients with Chronic kidney disease onMaintenance Hemodialysis.Method: This cross sectional observational study design was carried out through the present investigationfrom Jun 2nd January/2019 to2/July/2019 in order to achieve the objectives of the present study . A nonprobability(purposive)sample of 120 patient which including (86) males and (34) females. Who wereattending Hemodialysis Unit in AL- Hussein Teaching Hospital. The results according to the special criteria.Results: Total number of patients included in the study was 124 Mean age of all patients was 49.9±13.8 years,106 (84.8%) had hypertension, 84 (70%) had diabetes mellitus, and 35 (29.9%) had known cardiovasculardisease. Mean serum creatinine was 7.±3.4mg/dl, mean eGFR was 10.6±9.2 ml/min/1.73m2. Overall 78.4%of all CKD patients have one or more ECG abnormality. Left ventricular hypertrophy (40%), Q waves(27.2%), ST segment elevation or depression (23.4%), prolonged QRS duration (19.2%), tachycardia(17.6%) and left and right atrial enlargement (17.6%) were the most common abnormalities.Conclusion: ECG abnormalities are common in hospitalized CKD patients in local population. Allhospitalized CKD patients should undergo ECG to screen for cardiovascular disease.

Relationship between dialytic parameters and reviewer confirmed arrhythmias in hemodialysis patients in the monitoring in dialysis study

BackgroundHemodialysis patients have high rates of sudden death, but relationships between serum electrolytes, the dialysis prescription, and intra-dialytic shifts in fluid and electrolyte with arrhythmia are uncertain.MethodsWe analyzed sixty-six hemodialysis patients who underwent loop recorder implantation with continuous electrocardiographic monitoring, weekly to bi-weekly testing of pre- and post-dialysis electrolytes, and detailed capture of dialysis prescription and flow sheet data for 6 months. The incidence rate ratio (IRR) of reviewer confirmed arrhythmias (RCA) during dialysis through 8 h after dialysis and associations with serum chemistries and dialytic parameters were assessed using adjusted, negative-binomial regression.ResultsAmong 66 individuals with a mean age of 56 years, 12,480 events were detected in 64 (97%) patients. RCA nadired 12–24 h after dialysis and increased during the final 12 h of the inter-dialytic interval through the first 8 h after dialysis. Higher pre-dialysis serum magnesium concentration was associated with lower incidence rate ratio for arrythmia (IRR per 1 mg/dL increase 0.49, 95% CI; 0.25, 0.94), as was dialysate calcium concentration > 2.5 mEq/L vs. 2.5 mEq/L (IRR 0.52, 95% CI: 0.39, 0.70). Neither intradialytic serum potassium nor weight change were significantly associated with RCA rate. However, there was effect modification such that arrhythmia rate was maximal with concurrently high intradialytic volume and potassium removal (Pinteraction = 0.01).ConclusionsIntra and post-dialytic arrhythmias are common in hemodialysis. Additional studies designed to further elucidate whether modification of the serum magnesium concentration, dialysate calcium concentration, and the extent of intradialytic potassium and fluid removal reduces the risk of per-dialytic arrhythmia are warranted.Trial registrationClinicaltrials.gov NCT01779856. Prospectively registered on January 22, 2013.

Arrhythmia in hemodialysis patients and its relation to sudden death

Sudden death in patients on hemodialysis is believed to be due to arrhythmia, but the evidence for this is surprisingly limited. Five studies involving implantable loop recorders in patients on hemodialysis have now been published, and 4 have shown that bradyarrhythmia rather than tachyarrhythmia are the pre-eminent arrhythmic associations of fatal events. The Monitoring in Dialysis study, reported in this issue, sheds new light on the relationships of arrhythmia to the conventional 3-session weekly hemodialysis cycle.

Primary outcomes of the Monitoring in Dialysis Study indicate that clinically significant arrhythmias are common in hemodialysis patients and related to dialytic cycle

Sudden death is one of the more frequent causes of death for hemodialysis patients, but the underlying mechanisms, contribution of arrhythmia, and associations with serum chemistries or the dialysis procedure are incompletely understood. To study this, implantable loop recorders were utilized for continuous cardiac rhythm monitoring to detect clinically significant arrhythmias including sustained ventricular tachycardia, bradycardia, asystole, or symptomatic arrhythmias in hemodialysis patients over six months. Serum chemistries were tested pre- and post-dialysis at least weekly. Dialysis procedure data were collected at every session. Associations with clinically significant arrhythmias were assessed using negative binomial regression modeling. Sixty-six patients were implanted and 1678 events were recorded in 44 patients. The majority were bradycardias (1461), with 14 episodes of asystole and only one of sustained ventricular tachycardia. Atrial fibrillation, although not defined as clinically significant arrhythmias, was detected in 41% of patients. With thrice-weekly dialysis, the rate was highest during the first dialysis session of the week and was increased during the last 12 hours of each inter-dialytic interval, particularly the long interval. Among serum and dialytic parameters, only higher pre-dialysis serum sodium and dialysate calcium over 2.5 mEq/L were independently associated with clinically significant arrhythmias. Thus, clinically significant arrhythmias are common in hemodialysis patients, and bradycardia and asystole rather than ventricular tachycardia may be key causes of sudden death in hemodialysis patients. Associations with the temporal pattern of dialysis suggest that modification of current dialysis practices could reduce the incidence of sudden death.

Effects of L- and N-Type Ca Channel Blocker Cilnidipine on Changes in Heart Rate and QT Interval During Dialysis

Background/Aims: Hemodialysis patients have poor prognosis due to increased prevalence of cardiovascular diseases. Treatment to suppress increases in sympathetic nerve activity and QT prolongation may have the potential to reduce the occurrence of these events. The L/N-type Calcium (Ca) channel blocker cilnidipine has unique inhibitory action to inhibit sympathetic nerve activity and in a canine model ameliorates QT prolongation. In this study, we investigated whether cilnidipine has inhibitory effects on heart rate, an index of sympathetic nerve activity, and QT prolongation in patients undergoing dialysis. Methods: An L-type Ca channel blocker amlodipine was administered for 4 weeks followed by cilnidipine treatment for 4 weeks. On the last day of each period, heart rate and corrected QT interval were estimated and compared between the two periods. Results: Cilnidipine showed greater suppression of heart rate during dialysis than did amlodipine. The corrected QT interval in one dialysis session was significantly increased, and 3 of 17 patients showed prominent QT prolongation during administration of amlodipine but not cilnidipine. Conclusion: These data suggested that cilnidipine may inhibit increases in heart rate and QT interval. Cilnidipine may have beneficial effects in reducing cardiovascular events, resulting from increased sympathetic nerve activity and lethal arrhythmias in hemodialysis patients.

Cardiovascular and Stroke Risk in Japanese Hemodialysis Patients With Atrial Fibrillation.

Atrial fibrillation is one of the most common arrhythmias in hemodialysis patients. We evaluated its clinical outcomes among hemodialysis patients with atrial fibrillation in Japan. Using data derived from the Japanese Dialysis Outcomes and Practice Patterns Study, we analyzed backgrounds and outcomes among hemodialysis patients with and without atrial fibrillation in Japan. Among 7002 hemodialysis patients, the prevalence of atrial fibrillation was 5.7% and the incidence was 0.2 per 100 patient-years. Atrial fibrillation was independently associated with all-cause mortality (hazard ratio, 1.32; 95% confidence interval, 1.02-1.71) and cardiovascular events (hazard ratio, 1.39; 95% confidence interval, 1.15-1.68), but not with stroke events (hazard ratio, 0.77; 95% confidence interval, 0.55-1.06) after adjustment for other variables. We conclude that patients with atrial fibrillation experienced higher mortality and more cardiovascular events than did patients without atrial fibrillation, although the risk of stroke was lower than expected.

Outcomes of subcutaneous implantable cardioverter-defibrillator implantation in patients on hemodialysis.

Subcutaneous implantable cardioverter-defibrillator (S-ICD) provides potential benefits in patients on hemodialysis (HD) by reducing the risk of blood stream infection and preserving vascular access sites. We evaluated the safety and efficacy of S-ICD in patients with end-stage renal disease (ESRD) on HD. All consecutive patients implanted with S-ICD between October 2012 and April 2015 at our high-volume center were included in this retrospective, single-center study. Baseline demographics, procedural details, and short- as well as long-term outcomes were compared between patients on HD and not on HD. A total of 86 S-ICDs were implanted at our institution during the study period. Eighteen (21%) patients were on HD at the time of implant. HD patients were more likely to be implanted for secondary prevention. There was no statistically significant difference in procedural complications between the two groups. HD patients had a longer duration hospital stay after implant (3.6 ± 5.14 vs. 1.69 ± 2.29 days, p = 0.021). During a mean follow-up of 205 ± 208 days in the HD cohort and 242 ± 238 days in the non-HD cohort (p = 0.268), there was no device or blood stream infection in the HD group, compared with five device infections in the non-HD group. The incidence of inappropriate shocks was similar in both groups. All appropriate shocks were successful in terminating ventricular tachyarrhythmias in both groups. Patients on hemodialysis had worse inpatient as well as long-term mortality after S-ICD implant, compared with non-HD patients. Our study demonstrates the safety and efficacy of S-ICD in patients on HD. Despite representing a sicker patient population, HD patients implanted with S-ICD had similar procedural outcomes and inappropriate shocks. There was no device or blood stream-related infection in HD patients. All appropriate shocks for ventricular arrhythmias in HD patients were successful.

Arrhythmia and Sudden Death in Hemodialysis Patients: Protocol and Baseline Characteristics of the Monitoring in Dialysis Study.

Dialysis patients have high rates of cardiovascular morbidity and mortality, but data on arrhythmia burden, arrhythmia type, arrhythmia triggers, and the identity of terminal arrhythmias have historically been limited by an inability to monitor heart rhythm for prolonged periods. To investigate arrhythmia and its association with sudden death in dialysis-dependent ESRD, describe the potential for implantable devices to advance study of dialysis physiology, review the ethical implications of using implantable devices in clinical studies, and report on the protocol and baseline results of the Monitoring in Dialysis Study (MiD). In this multicenter, interventional-observational, prospective cohort study, we placed implantable loop recorders in patients undergoing long-term hemodialysis. The proportion of patients experiencing clinically significant arrhythmias was the primary endpoint. For 6 months, we captured detailed data on the primary endpoint, symptomatic arrhythmias, other electrocardiographic variables, dialysis prescription, electrolytes, dialysis-related variables, and vital signs. We collected additional electrocardiographic data for up to 1 year. Overall, 66 patients underwent implantation in sites in the United States and India. Diabetes was present in 63.6% of patients, 12.1% were age ≥70 years, 69.7% were men, and 53.0% were black. Primary and secondary endpoint data are expected in 2016. Cardiac arrhythmia is an important contributor to cardiovascular morbidity and mortality in dialysis patients, but available technology has previously limited the ability to estimate its true burden and triggers and to define terminal rhythms in sudden death. Use of implantable technology in observational studies raises complex issues but may greatly expand understanding of dialysis physiology. The use of implantable loop recorders in MiD is among the first examples of such a trial, and the results are expected to provide novel insights into the nature of arrhythmia in hemodialysis patients.

The Comparison of Four Different Dialysates on QT Dispersion and Arrhythmias in Hemodialysis Patients

The Comparison of Four Different Dialysates on QT Dispersion and Arrhythmias in Hemodialysis Patients

Atrial Fibrillation in Chronic Hemodialysis Patients: Prevalence, Types, Predictors, and Treatment Practices in Greece

Atrial fibrillation (AF), the most common sustained arrhythmia in clinical practice, is associated with increased mortality and cardiovascular morbidity both in nonuremic and (recently) in dialysis patients. The aims of this study are: (i) to assess the prevalence of AF, the risk factors, and predictors of its presence in a cohort of incident hemodialysis (HD) patients in Greece and (ii) to report on current practices in the management of these patients. This is a prospective, cross-sectional, multicenter study of 574 patients on a regular HD program for >6 months. Demographic characteristics, cause of renal disease, cardiovascular risk factors, medication use, dialysis data (Kt/V, dialysis method, type of dialysate), 12-lead electrocardiogram (ECG) (interdialytic day), and cardiac echo data were collected. Pertinent demographic, ECG, and echocardiographic data were entered into univariate and multivariate analyses to evaluate associations with AF. The CHADS2 score (congestive heart failure [HF], hypertension, age ≥ 75, diabetes, previous stroke/transient ischemic attack [TIA]) was estimated and clinical practices in high-risk (CHADS2 score ≥ 2) patients were evaluated. The cohort included 368 men (64.1%) and 206 (35.8%) women (mean age 65.1 ± 14.4 years) with a mean duration on dialysis of 72.1 ± 60.4 months. Hypertension (75.6%) and coronary artery disease (47.2%) were the commonest cardiovascular risk factors for AF. The prevalence of AF was 23.2% and showed an age-dependent increase; in patients <50 years, AF was present in 9.3%, while in patients ≥ 80 years, its prevalence increased to 36.4%. Furthermore, 8.3% of patients had permanent, 1.8% persistent, 12.7% paroxysmal AF, while the prevalence of paroxysmal atrial flutter and sick sinus syndrome were 1.2 and 2%, respectively. Logistic regression analysis showed that age, smoking, left atrial and aortic root diameter, β-blocker and α-calcidol use, HF, and the presence of valvular calcifications (VC) on cardiac echo were independently associated to the presence of AF. VC on cardiac echo had an almost sevenfold increased association with AF (odds ratio 6.72, 95% confidence interval 3.23-13.98, P < 0.0001). Only 25.5% of high-risk (CHADS2 score ≥ 2) patients were receiving anticoagulants. AF is a frequent arrhythmia in HD patients. Apart from well-known risk factors, VC merits special attention in this patient population. Less than one-third of high-risk AF patients receive anticoagulants, possibly reflecting the absence of definite guidelines for the management of AF in HD patients.

Severe coronary stenosis is an important factor for induction and lengthy persistence of ventricular arrhythmias during and after hemodialysis

Background: Ventricular arrhythmias have been shown to be the major cause of sudden cardiac death in hemodialysis (HD) patients. We investigated whether angiographic coronary stenosis was responsible for the induction of ventricular arrhythmias in HD patients. Methods: HD patients (n = 150) showing ischemic signs in exercise electrocardiography or echocardiography were divided into 2 groups: the stenotic group (n = 61), with significant coronary stenosis (≥75% in diameter), and the nonstenotic group (n = 89), without significant coronary stenosis on coronary angiography. Severity of ventricular arrhythmias was evaluated by means of ambulatory 24-hour Holter monitoring in HD patients with and without significant coronary stenosis. Results: The frequency of ventricular premature contractions and prevalence of patients with Lown class 4 ventricular arrhythmias were significantly greater in the stenotic than nonstenotic group during HD and for 12 hours after HD (P < 0.03). In the stenotic group, a significantly greater frequency of ventricular premature contractions and prevalence of patients with complex arrhythmias were observed during HD (1.33% and 31.1%, respectively) compared with before HD (0.50% and 11.5%, respectively), and the high incidence persisted for 6 hours after HD. In the nonstenotic group, a slightly increased incidence was observed only during HD compared with before HD. Multivariate analysis showed only coronary stenosis (odds ratio, 5.69; P = 0.041) as an independent and significant factor for the induction of complex arrhythmias. Conclusion: These data clearly indicate that severe coronary stenosis, which may cause myocardial ischemia, is an important factor for the induction and lengthy persistence of ventricular arrhythmias during and after HD.

QT Dispersion in Hemodialysis and CAPD Patients

Prolongation of repolarization dispersion (QT interval dispersion) measured from the 12-lead surface ECG has been associated with sudden cardiac death and ventricular tachyarrhythmias in a variety of cardiac disorders. The aim of our study was to assess the effects of hemodialysis (HD) and continuous ambulatory peritoneal dialysis (CAPD) on QT dispersion in end-stage renal disease patients. 20 chronic HD patients (mean age 57.75 ± 13.79 years) and 20 CAPD patients (mean age 50.79 ± 14.94 years) who had no complaints and symptoms of cardiac arrhythmias as well as 20 healthy volunteers (mean age 48.74 ± 10.88 years) underwent ECG testing. All HD patients were on bicarbonate three times weekly with cuprophane capillaries. 12-lead ECGs were recorded on the day after HD. The CAPD patients were on a standard CAPD program (four times daily with 2,000 cm³ peritoneal fluid). ECGs were recorded when the patients were receiving their regular standard CAPD program. All ECGs were analyzed manually by one observer. There were no statistically significant differences in dialysis duration, blood urea nitrogen, creatinine, sodium, calcium, and parathormone values between the HD and CAPD patients. The serum potassium values were significantly higher in HD patients when compared to CAPD patients. There was no difference in the mean of maximal QT among all three groups. The rate of QT interval dispersions was significantly higher in HD and CAPD patients as compared with healthy controls (p < 0.05). There was no statistically significant difference in the QT dispersion rates between HD and CAPD patients. In conclusion, there is a tendency to cardiac arrhythmias in HD patients during the postdialysis period. Although CAPD patients are receiving dialysis daily, they also have higher rates of QT dispersions and accordingly a tendency to arrhythmias.

SYMPTOMATIC ATRIAL ARRHYTHMIAS IN HEMODIALYSIS PATIENTS

Background/Aims: Cardiac arrhythmias are frequent in hemodialysis patients and can interrupt treatment. However, the frequency and risk factors have remained unclear because previous reports of arrhythmias in dialysis patients have usually been continuous-monitoring studies that looked at all cardiac ectopy regardless of its seriousness. Methods: We reviewed retrospectively only symptomatic atrial arrhythmias in a population of 106 maintenance hemodialysis patients over three years, in order to estimate their actual frequency and any risk factors. Results: Ten patients, seven men and three women, required treatment for atrial arrhythmias (9.4%): four for supraventricular tachycardia, three for atrial flutter, and three for atrial fibrillation. Their mean age was 53.7 ± 6.1 years; five of them were ≤40 years. Seven arrhythmias were new, three were recurrences. All but one occurred between 3 and 4 hours of hemodialysis, and dialysis had to be stopped in nine instances. There was no pattern of hypotensive episodes preceding the arrhythmias. Mean serum K+ drawn at the time of the arrhythmias was 3.8 ± 0.2 mEq/L. Mean plasma intact parathormone was 1128 ± 417 pg/mL, compared to 454 ± 58 pg/mL for our entire hemodialysis population (p = .0036). Subsequent echocardiograms showed abnormalities in 9/10 patients: five had left ventricular hypertrophy, six had left atrial enlargement, five had valvular lesions (four mitral regurgitation; one aortic incompetence), and three had ejection fractions <50%. There were four deaths in these patients over the next 14 months, but probably only one was cardiac. Conclusions: Serious atrial arrhythmias are common in a hemodialysis population. Risk factors for symptomatic atrial arrhythmias in hemodialysis patients may include hyperparathyroidism and echocardiographic findings of chamber enlargement, valvular lesions, or ventricular dysfunction.

Clinical Pharmacokinetics and Effects of an Oral Sustained-Release Preparation of Disopyramide Prescribed for Patients Undergoing Maintenance Hemodialysis

Aims: We evaluated the clinical pharmacokinetics of a sustained-release preparation of disopyramide phosphate (DSR) and its effects on supraventricular arrhythmias in hemodialysis patients. Methods: Eight hemodialysis patients with either paroxysmal supraventricular tachycardia (PSVT) or PSVT plus paroxysmal atrial fibrillation (Paf) were given 150 mg of DSR 2 h before each hemodialysis. The frequency of PSVT, the duration of Paf before and 2 weeks after starting DSR and the blood concentration of the drug were evaluated. Results: There was no significant difference between serum levels of DSR before and after hemodialysis. The frequency of PSVT and the duration of Paf were significantly reduced by the therapy. Side effects and electrocardiographic abnormalities did not appear during the period. Conclusion: We conclude that hemodialysis does not remove DSR, and that a single dose of 150 mg of DSR given 2 h before hemodialysis is safe and sufficient to reduce the incidence of supraventricular arrhythmias.

Left Ventricular Hypertrophy as a Risk Factor for Arrhythmias in Hemodialysis Patients

The contribution of left ventricular hypertrophy in determining ventricular arrhythmias (VAS) was studied in 81 chronic renal failure patients in chronic hemodialysis using two-dimensional echocardiographic and electrocardiogram Holter monitoring. The prevalence of LVH was 93% (96% in hypertensive and 87% in normotensive patients). The prevalence of VA was 48%. These arrhythmias were associated with increased cardiac mass, lack of potassium supplementation to the hemodialysis bath, and low K+ and PaO2 during dialysis. Severe forms of VA occurred in 19 of 78 patients, and the risk factors for this occurrence were (a) largely increased cardiac mass indices (exceeding in more than 40% the upper limit of normal for each sex) and (b) prolonged periods of time in hemodialysis treatment (34 +/- 5.5 vs. 17 +/- 2.7 months, p less than 0.05). Changes in potassium or oxygen content of the blood were not significantly associated with the occurrence of severe forms of VA.