Permanent cardiac pacing after a cardiac operation: predicting the use of permanent pacemakers

BACKGROUND: The need for permanent cardiac pacing after cardiac operations is infrequent but associated with increased morbidity and resource utilization. We identified patient risk factors for pacemaker insertion to enable development of a predictive model. METHODS: Data were collected prospectively for 10,421 consecutive patients who had cardiac operations between January 1990 and December 1995. Two hundred fifty-five patients (2.4%) were identified as having received a permanent pacemaker during the same hospitalization. Logistic regression analysis was performed to determine the independent, multivariate predictors of permanent pacing. The predictive accuracy and precision of the logistic regression model was evaluated in the 1996 database of 2,236 consecutive patients by the calculation of Brier scores. RESULTS: Eight independent predictors of permanent pacemaker requirement were identified. The factor-adjusted odds ratios (OR) with 95% confidence interval (CI) associated with each predictor are as follows: (1) valve replacement surgery (aortic: OR 5.8, CI 3.9-8.7; mitral: OR 4.9, CI 3.1-7.8; tricuspid: OR 8.0, CI 5.5-11.9; double: OR 8.9, CI 5.5-14.6; and triple: OR 7.5, CI 2.9-19.3); (2) repeat operation: OR 2.4, CI 1.8-3.3; (3) age 75 years or older: OR 3.0, CI 2.0-4.4; (4) ablative arrhythmia operation: OR 4.2, CI 1.9-9.5; (5) mitral valve annular reconstruction: OR 2.4, CI 1.4-4.2; (6) use of cold blood cardioplegia: OR 2.0, CI 1.2-3.6; (7) preoperative renal failure: OR 1.6, CI 1.0-2.6; and (8) active endocarditis: OR 1.7, CI 0.9-3.0. A model for postoperative permanent pacemaker requirement using the eight predictors was formulated and tested (Brier score = 0.017+/-0.003; Z = 0.18). CONCLUSIONS: The proposed predictive model correlated highly with actual pacemaker use, which suggests that the requirement for pacing results from either operative trauma or increased ischemic burden. Preoperative identification of patients at increased risk of conduction disturbances may allow for earlier detection and improved treatment. Patients requiring postoperative pacing had increased morbidity and length of stay.     

Subclavian vein catheterisation for cardiac surgery in children

Infraclavicular subclavian vein catheterisation is a useful means of measuring central venous pressure and establishing a central infusion line in children undergoing open heart surgery. In 48 children ranging in age from 15 months to 13 years, there was a high success rate and no morbidity.     

Psychiatric morbidity and depressive symptomatology in patients with permanent pacemakers

Implantation of a permanent pacemaker requires a psychological effort on the patient's part for adaptation in the acute term, and chronically, it restricts activities of the patient and may cause some psychiatric disturbances. To investigate psychiatric morbidity and depressive symptomatology of the patients with permanent pacemakers, 84 pacemaker patients were diagnosed using the DSM-III-R criteria and depressive symptoms were determined by modified Hamilton Depression Rating Scale (mHDRS). Sixteen (19.1%) patients had been given a psychiatric diagnosis. The most frequent diagnoses were adjustment disorder (5.9%) and major depressive episode (4.7%). Nine patients (10.7%) were diagnosed as having clinical depression (mHDRS > or = 17). The mean score of mHDRS was 7.57 +/- 7.46, and the severity of depression was significantly higher in females. The most frequent symptoms are difficulties in work and activities (53.6%), psychic anxiety (48.8%), loss of energy (42.9%), and hypochondriasis and insomnia (39.3%). Depressed mood, psychic anxiety, loss of energy, loss of interest, insomnia, and hypochondriasis were significantly more frequent in females. Uneducated patients had a more significant loss of energy than educated patients. Depressed mood, psychic anxiety, and somatic concerns and symptoms were more frequent in patients with permanent pacemakers than in the general population. These symptoms, resembling mixed anxiety-depression disorder, were related to fears of having a permanent pacemaker, since our series were composed of uneducated patients who did not have enough knowledge about the device.     

Atrial fibrillation and anticoagulation in patients with permanent pacemakers: implications for stroke prevention

Several large prospective randomized trials have demonstrated that anticoagulation with warfarin reduces the risk of thromboembolic stroke in high risk patients with chronic AF by approximately 70%. Large numbers of patients with permanent pacemakers have AF, and anticoagulation rates in this population have not been described. In a prospective analysis of 110 consecutive patients attending the pacemaker clinic of a large university hospital we assessed the number of patients with AF and the proportion of these patients who were receiving anticoagulation to prevent thromboembolic stroke. Where necessary, temporary pacemaker reprogramming to low ventricular rates was utilized to facilitate the diagnosis of AF. Fifty-three of the 110 patients (48%) were diagnosed with AF, all of whom (100%) had accepted high risk factors for thromboembolic stroke. Only eight of the 53 (15%) had been anticoagulated with warfarin. Thirty-six of the 53 patients (68%) diagnosed with AF had no prior documented diagnosis of chronic AF, and the majority had no symptoms suggesting AF. A single lead II ECG was insufficient in 67 of the 110 patients (61%) to diagnose the underlying atrial rhythm; the remainder required 12-lead ECGs or temporary pacemaker reprogramming to low ventricular rates to diagnose the underlying atrial rhythm. AF is common in patients with permanent pacemakers. It is commonly asymptomatic, and anticoagulation is markedly underutilized in reducing stroke risk in these patients. Attention to the possibility of AF in paced patients should allow prompt diagnosis and allow both the initiation of anticoagulation in order to reduce thromboembolic stroke risk and consideration for cardioversion of AF to sinus rhythm.     

Transurethral resection in patients with cardiac pacemakers (author''s transl)

Problems of transurethral resection in patients with cardiac pacemakers are discussed. Various complications caused by interference of cutting and coagulating currents with the pacemaker system and their possible prevention are pointed out. It is concluded that transurethral resection by cold punch technique has significant advantages over electroresection in patients with a cardiac pacemaker.     

Factors associated with atrial fibrillation in patients with mitral stenosis: a cardiac catheterization study

OBJECTIVE: The aim of this study was to characterize the adenosine A3 receptor agonist, N6-(3-chlorobenzyl)-5'-N-methylcarboxamidoadenosine (CB-MECA), evaluate its ability to reduce myocardial ischemia/reperfusion injury and determine the role of KATP-channel activation in A3 receptor-mediated cardioprotection. METHODS: Binding affinities and adenylate cyclase inhibition were examined in CHO cells expressing rabbit recombinant adenosine A1 or A3 receptors. Infarct size (normalized for area-at-risk; % IA/AAR) was measured in buffer-perfused rabbit hearts exposed to 30-min regional ischemia and 120 min of reperfusion. RESULTS: CB-MECA was 100-fold selective for A3 vs. A1 receptors (A3 Ki: 1 nM; A1 Ki: 105 nM). Five-min perfusion with CB-MECA before ischemia/reperfusion elicited a concentration-dependent reduction in infarct size (EC50: 0.3 nM). The CB-MECA-dependent cardioprotection (control: 58 +/- 2; CB-MECA: 21 +/- 3% IA/AAR) was unchanged by an A1-selective concentration of the antagonist, BWA1433, but was completely prevented (P < 0.05) by a nonselective (A1/A3) concentration (55 +/- 6% IA/AAR). The KATP channel inhibitors, glibenclamide and 5-HD, had no effect on control infarct size, yet significantly (P < 0.05) blunted the CB-MECA-dependent cardioprotection (glibenclamide: 49 +/- 6; 5-HD: 58 +/- 4% IA/AAR). CONCLUSIONS: CB-MECA is a novel 100-fold A3 receptor-selective agonist which should prove useful for elucidating A3-dependent mechanisms in the rabbit heart. Selective stimulation of adenosine A3 receptors with CB-MECA reduces myocardial ischemia/reperfusion injury via a mechanism which involves activation of KATP channels.     

Colonization with vancomycin-resistant enterococci in chronic hemodialysis patients

OBJECTIVE: To identify the prevalence of chorioaminionitis and unique risk factors for this disorder among adolescents under 18 years of age. METHODS: At their first prenatal visit we interviewed 352 adolescents who received prenatal care and delivered an infant at our institution between April 20, 1992, and November 10, 1994, to elicit information on demographic characteristics and behavioral risk factors. Retrospective chart review confirmed the presence of chorioamnionitis using accepted clinical criteria. We determined reproductive history, evidence of sexually transmitted disease, duration of labor, use of oxytocin, an internal uterine pressure monitor or conduction anesthesia, timing and duration of ruptured membranes, type of delivery, and infant birth weight from review of subjects' charts. Logistic regression analysis was used to develop adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for risk factors of chorioaminionitis. RESULTS: Ten percent (34 of 352) of adolescents met the clinical definition for chorioamnionitis. Alcohol and tobacco use during pregnancy (OR 7.6; 95% CI 2.3, 25.8) and being married or living with a partner (OR 2.7; 95% CI 1.1, 6.5) were significantly associated with chorioamnionitis, as was conduction anesthesia (OR 4.1; 95% CI 1.1, 15.4), a second stage labor longer than 2 hours (OR 3.5; 95% CI 1.4, 8.5), and rupture of the membranes longer than 18 hours (OR 6.9; 95% CI 2.5, 18.9). Parity or preterm delivery did not differ significantly between those with or without chorioamnionitis. CONCLUSION: These data suggest that in addition to risk factors observed in adults, adolescents who concurrently use tobacco and alcohol during pregnancy, are married or living with a male partner, and have conduction anesthesia are at increased risk for chorioamnionitis.     

Glossopharyngeal neuralgia with cardiac syncope: treatment with a permanent cardiac pacemaker and carbamazepine

Cardiac synope was associated with glossopharyngeal neuralgia in an elderly woman. The patient also manifested severe carotid sinus sensitivity. Permanent demand pacemaker and carbamazepine therapy were used successfully to alleviate the symptoms.     

Diastolic dysfunction in patients with chronic kidney failure on a hemodialysis program

OBJECTIVE: The aim of this study was to analyse different ultrasound parameters for the assessment of isolated left ventricular diastolic dysfunction (LVDD) in patients with chronic renal failure (CRF) on periodic hemodialysis (HD), comparing pulsed wave Doppler with pulsed tissue Doppler. MATERIALS AND METHODS: Forty-seven patients with CRF on HD (61% were male; mean age was 51.0 +/- 16.5 years, mean HD time--3.7 +/- 3.8 years, 38% had hypertension, 17% had diabetes) were studied by echocardiography (bidimensional, M-Mode, flow pulsed Doppler and tissue Doppler imaging). All patients had symptoms of left heart failure-class II NYHA, were in sinus rhythm and had no symptoms of ischemic heart disease. The presence of abnormal LV regional contractility was the exclusion criteria. According to their mitral inflow profile Doppler characteristics, patients were included in two groups: Group A (E/A > 1; n = 21) and B (E/A < 1; n = 26). We compared: LV dimensions and function, left atrial (LA) dimension. Gaasch index, LV mass index. E and A wave velocities (in flow pulsatile Doppler and tissue Doppler). E/N ratio in tissue Doppler, isovolumetric relaxation time (IVRT) and deceleration time (DT). RESULTS: There were no significant differences in the prevalence of age > or = 65 years male sex, hypertension or diabetes between group A and B patients, and almost all patients were on hemodialytic treatment for more than one year (81% vs 85%: NS). LV hypertrophy was present in almost all group A and B patients (A--95% vs B--85.5%; NS). Group A, compared with group B, had a difference in the Gaasch index (2.45 +/- 0.3 vs 2.08 +/- 0.4; p < 0.05), E wave velocity in flow pulsatile Doppler and tissue Doppler (cm/sec) (110 +/- 27 vs 62 +/- 20; p < 0.001 and 41 +/- 15 vs 28.5 +/- 16; p < 0.05), E/A ratio in tissue Doppler (1.3 +/- 0.4 vs 0.8 +/- 0.3; p < 0.001). IVRT (msec) (80.7 +/- 15.2 vs 113.5 +/- 28.3; p < 0.001) and DT (msec) (189.7 +/- 24 vs 278.2 +/- 17.9; p < 0.001). According to the E'/A' ratio in tissue Doppler, group A patients were divided in another two groups: E'/A' > 1 (13/21--62%) and < 1 (8/21--38%) and a significantly longer IVRT (75.8 +/- 9.3 vs 100.9 +/- 3.2; p < 0.001) and DT (178 +/- 15 vs 240 +/- 20; p < 0.001) and a greater LA dimension (37.6 +/- 6.9 vs 44.6 +/- 6.9; p < 0.05) were found. CONCLUSIONS: Pulsed wave Doppler is the most useful non invasive method for assessment of global diastolic dysfunction. In our study, 17% of the patients had E/A < 1 only in the tissue Doppler study. These patients probably had a pseudonormal mitral pattern.     

Permanent cardiac pacemakers in children: technical considerations

Placement of permanent cardiac pacemakers in children presents technical problems that are not encountered in the adult. Problems unique to pacemaker implantation in children are related to the patient's size, the relative bulkiness of pulse generators, the lack of subcutaneous tissue, and the child's growth and long life expectancy. Based on our experience with implantation of 27 permanent cardiac pacemakers in 13 children, we have found that the use of small pulse generators, placement of epicardial leads, insertion of properitoneal pulse generators, and use of recharabeable pacemakers are satisfactory methods in children.     

Lipid status in patients on a chronic hemodialysis program

Dyslipidemia causes development of atherosclerosis in chronic hemodialysis patients. The goal of this study was to determine values of serum lipids in hemodialysis patients. The study comprised 45 patients, whereas the control group consisted of 45 healthy persons of corresponding age and sex. We determined triacyglycerols, total cholesterol, HDL (high density lipoprotein) and LDL (low density lipoprotein) cholesterol in the serum of patients on an empty stomach. There were 51% of patients with normal findings, and 49% with hyperlipoproteinemia type IV. In regard to the control group triacyglycerol was increased both in patients with hyperlipoproteinemia type IV and in patients with normolipemia. Levels of total cholesterol were higher in patients with hyperlipoproteinemia type IV, while values of HDL cholesterol were decreased in both subgroups of patients in regard to the control group. Values of total cholesterol in relation to HDL cholesterol > 4.5 occurred in 38% of patients. Lipid profile of hemodialysis patients, including those with normolipidemia, points to high risk of cardiovascular diseases.     

Patch migration: a serious late complication of thoracotomy lead systems

Thoracotomy patch leads used for implantable cardioverter defibrillators (ICDs) are generally safe and effective. We describe two patients in whom a late complication of patch lead migration occurred years after the original implants, causing a bronchopleural fistula in one and lingular lobe collapse in the other patient. We conclude that patch migration is a late but possible complication of extrapericardial ICD leads, and should be suspected in patients who present with hemoptysis, atypical pneumonia, or lung collapse after the initial ICD surgery.     

Toxic methemoglobinemia: a rare but serious complication of transesophageal echocardiography

Cyanosis occurring during a transesophageal echocardiogram (TEE) is usually related to the respiratory depressant effect of the administered sedative. However, acute toxic methemoglobinemia related to topical benzocaine is a rare and not well recognized but potentially life threatening cause of cyanosis during or after TEE. A case of this condition is presented and the literature on its frequency, diagnosis and management is briefly reviewed.     

Subglottic stenosis in a child: a complication of prolonged endotracheal intubation

A case of septicemia and meningitis due to Streptococcus zooepidemicus in an immunocompetent patient is reported. This organism is an uncommon human pathogen that sometimes causes severe infection, usually in immunocompromised patients. In the reported case, the patient required to be mechanically ventilated for one week and was treated with intravenous ampicillin and gentamicin. He recovered and was discharged from hospital three weeks after the initial presentation. Streptococcus zooepidemicus sensitive to all penicillins, was isolated from all blood cultures and the cerebrospinal fluid.     

Coronary artery stenosis in Reiter's syndrome: a complication of aortitis

Seronegative spondyloarthritis may be complicated by a variety of cardiac lesions including aortitis. We describe a patient with Reiter's syndrome who presented with angina and new onset heart murmurs. Cardiac catheterization revealed myocardial ischemia and aortic insufficiency. Our patient underwent bypass surgery with aortic valve replacement. Severe narrowing of the coronary ostia was noted and aortitis was documented by pathologic examination.     

Serum vanadium levels in chronic hemodialysis patients

Serum vanadium, aluminum, silicon and beta 2-microglobulin levels as well as the red cell count, hemoglobin and systolic blood pressure were simultaneously measured in 80 chronic hemodialysis patients. The serum vanadium level was positively correlated with the serum levels of aluminum, silicon and beta 2-microglobulin as well as the systolic blood pressure, and was inversely correlated with the red cell count and hemoglobin. The mean serum vanadium level was 18.4 +/- 7.6 ng/ml before hemodialysis and decreased to 13.0 +/- 5.30 ng/ml at the completion of dialysis. The dialysate vanadium level increased from 0.4 +/- 0.2 (inflow) to 1.0 +/- 0.4 ng/ml (outflow). It was concluded that vanadium was transferred from blood to dialysate when purified water was used in the preparation of the dialysate.