Renal amyloidosis in a drug abuser

Drug abusers, particularly those who inject drugs s.c. ("skin popping"), may develop amyloidosis. Chronic infections are thought to play a pathogenetic role in this setting. A patient is presented who had a history of "skin popping" cocaine and heroin and developed nephrotic syndrome, with an elevated serum creatinine and a creatinine clearance of 61 mL/min. Renal biopsy demonstrated amyloidosis. Treatment with colchicine was initiated, and proteinuria decreased to near normal levels after 12 months. Concomitant with the decrease in proteinuria, creatinine clearance improved, although a repeat renal biopsy failed to show any significant improvement in amyloid burden. These observations suggest that colchicine may be a useful treatment in reversing the proteinuria of renal amyloidosis associated with drug abuse. Furthermore, clinical improvement may occur before any demonstrable regression in the amyloidosis.     

Unusual left atrial mass following cardiac surgery in an infant

An unexpected left atrial mass was found during routine postoperative transthoracic echocardiogram in an infant following surgical closure of ventricular septal defect. Thrombus could not be excluded. At reoperation it was found to be an inverted left atrial appendage. This case demonstrates the echocardiographic appearance of an inverted left atrial appendage.     

Nonsurgical cure of isolated cerebral mucormycosis in an intravenous drug user

The case of a 30-year-old, female, HIV-positive intravenous drug user who suffered from isolated cerebral mucormycosis is reported. Treatment with amphotericin B at an accumulative dose of 5.5 grams led to significant recovery, and there was no recurrence of disease over a follow-up period of six months. Patients with isolated cerebral mucormycosis in whom surgery would be a high-risk or impossible procedure could be managed medically with prolonged courses of intravenous amphotericin B.     

Combined use of left atrial transesophageal pacing and cordarone in atrial flutter

AIM: To investigate the effectiveness of superfrequent transesophageal left atrial stimulation (TLAS) and its combination with cordarone in management of atrial flutter (AF). MATERIALS AND METHODS: 650 patients with paroxysmal AF underwent TLAS. The paroxysm duration varied from 1 hour to 1 month. In 312 patients TLAS was performed prior to treatment with antiarrhythmic drugs (group 1), in 338 patients--after intravenous administration of cordarone (group 2). RESULTS: Superfrequent TLAS has restored sinus rhythm (SR) in 85(27.2%) and 169(50%) patients of groups 1 and 2, respectively (p < 0.001). TLAS promoted conversion of AF in atrial fibrillation (AFi) in 185(59.3%) and 159(47.1%) patients of groups 1 and 2, respectively (p < 0.01). Moreover, SR recovered 24-48 hours after TLAS in 87(27.9%) and 64(18.9%) patients of groups 1 and 2 respectively (p < 0.01). Sinus rhythm recovered in a total of 172(55.1%) and 233(69.0%) patients, AF was converted to AFi in a total of 88(31.4%) and 95(28.1%) patients (p > 0.05) of groups 1 and 2, respectively. TLAS was uneffective in 42(13.5%) and 10(2.9%) patients of groups 1 and 2, respectively. CONCLUSION: Superfrequent TLAS is a highly effective and non-invasive modality in the treatment of paroxysmal AF. It promotes recovery of SR. In some patients TLAS induces AFi which is more controllable by medication as regards the heart rate. Cordarone contributes to the response to TLAS in patients with paroxysmal AF.     

Disappearing subdural hematomas in children

Serum glucose and plasma C-peptide response to i.v. glucagon administration was evaluated in 24 healthy dogs, 12 dogs with untreated diabetes mellitus, 30 dogs with insulin-treated diabetes mellitus, and 8 dogs with naturally acquired hyperadrenocorticism. Serum insulin response also was evaluated in all dogs, except 20 insulin-treated diabetic dogs. Blood samples for serum glucose, serum insulin, and plasma C-peptide determinations were collected immediately before and 5, 10, 20, 30, and (for healthy dogs) 60 minutes after i.v. administration of 1 mg glucagon per dog. In healthy dogs, the patterns of glucagon-stimulated changes in plasma C-peptide and serum insulin concentrations were identical, with single peaks in plasma C-peptide and serum insulin concentrations observed approximately 15 minutes after i.v. glucagon administration. Mean plasma C-peptide and serum insulin concentrations in untreated diabetic dogs, and mean plasma C-peptide concentration in insulin-treated diabetic dogs did not increase significantly after i.v. glucagon administration. The validity of serum insulin concentration results was questionable in 10 insulin-treated diabetic dogs, possibly because of anti-insulin antibody interference with the insulin radioimmunoassay. Plasma C-peptide and serum insulin concentrations were significantly increased (P < .001) at all blood sampling times after glucagon administration in dogs with hyperadrenocorticism, compared with healthy dogs, and untreated and insulin-treated diabetic dogs. Five-minute C-peptide increment, C-peptide peak response, total C-peptide secretion, and, for untreated diabetic dogs, insulin peak response and total insulin secretion were significantly lower (P < .00l) in diabetic dogs, compared with healthy dogs, whereas these same parameters were significantly increased (P < .01) in dogs with hyperadrenocorticism, compared with healthy dogs, and untreated and insulin-treated diabetic dogs. Although not statistically significant, there was a trend for higher plasma C-peptide concentrations in untreated diabetic dogs compared with insulin-treated diabetic dogs during the glucagon stimulation test. Baseline C-peptide concentrations also were significantly higher (P < .05) in diabetic dogs treated with insulin for less than 6 months, compared with diabetic dogs treated for longer than 1 year. Finally, 7 of 42 diabetic dogs had baseline plasma C-peptide concentrations greater than 2 SD (ie, > 0.29 pmol/mL) above the normal mean plasma C-peptide concentration; values that were significantly higher, compared with the results in healthy dogs (P < .001) and with the other 35 diabetic dogs (P < .001). In summary, measurement of plasma C-peptide concentration during glucagon stimulation testing allowed differentiation among healthy dogs, dogs with impaired beta-cell function (ie, diabetes mellitus), and dogs with increased beta-cell responsiveness to glucagon (ie, insulin resistance). Plasma C-peptide concentrations during glucagon stimulation testing were variable in diabetic dogs and may represent dogs with type-1 and type-2 diabetes or, more likely, differences in severity of beta-cell loss in dogs with type-1 diabetes.     

Blood lead of intravenous drug users

Ethanol, morphine, cocaine and amphetamine were examined in place conditioning. After determination of initial preferences, animals were conditioned with ethanol (1 g/kg), morphine (5 mg/kg), cocaine (5 mg/kg) and amphetamine (5 mg/kg) alone or with combinations of these drugs plus naloxone (1 mg/kg). Naloxone prevented the ability of all drugs used to produce a place preference. The reinforcing properties of ethanol and morphine were reduced by sodium nitroprusside at a dose equal to 1/10 of LD50 given before preference testing. Molsidomine (1/10 LD50 and 1/20 LD50) altered the expression of the conditioned place preference produced by ethanol but not by morphine. Results of the present study suggest the involvement of endogenous opioids and probably of nitric oxide in the rewarding actions of drugs of abuse.     

Echocardiographic findings in left ventricular to right atrial shunts

The echocardiographic abnormalities of tricuspid valve motion in 2 patients with left ventricular to right atrial shunts are described. In both patients the abnormal anatomy was defined at surgery, in one patient the shunt being above the tricuspid valve leaflets (supravalvar) and in the other patient through the septal leaflet (intravalvar). Different patterns of tricuspid valve systolic fluttering were seen in these two cases and the possible reasons for this are discussed. After surgical closure of the defects the systolic fluttering of the tricuspid valve was no longer observed. Echocardiography appears to be useful in detecting the presence of left ventricular to right atrial shunts which otherwise may be difficult to diagnose.     

Effects of left atrial dilatation on the endocardial atrial defibrillation threshold: a study in an ovine model of pacing induced dilated cardiomyopathy

Left atrial (LA) dilation is a common finding in patients with chronic atrial fibrillation (AF). Progressive dilatation may alter the atrial defibrillation threshold (ADFT). In our study, epicardial electrodes were implanted on the LA free wall and right ventricular apex of eight adult sheep. Large surface area, coiled endocardial electrodes were positioned in the coronary sinus and right atrium (RA). LA dilatation was induced by rapid ventricular pacing (190 beats/min) for 6 weeks and echocardiographically assessed weekly along with the ADFT (under propofol anesthesia). LA effective refractory period (ERP) was measured every 2-3 days using a standard extra stimulus technique and 400 ms drive. The AF cycle length (AFCL) was assessed from LA electrograms. During the 6 weeks of pacing the mean LA area increased from 6.1 +/- 1.5 to 21.3 +/- 2.4 cm2. There were no significant changes in the mean ADFT (122 +/- 15 V), circuit impedance (46 +/- 5 omega), or LA AFCL (136 +/- 23 ms). There was a significant increase in the mean LA ERP (106 +/- 10 ms at day 0, and 120 +/- 13 ms at day 42 of pacing). In this study, using chronically implanted defibrillation leads, the minimal energy requirements for successful AF were not significantly altered by ongoing left atrial dilatation. This finding is a further endorsement of the efficiency of the coronary sinus/RA shock vector. Furthermore, the apparent stability of the AF present may be a further indication of a link between the type of AF and the ADFT.     

Video-assisted minimal access in excision of left atrial myxoma

BACKGROUND: Minimal access surgery with video-assisted endoscopy has been applied to the correction of intracardiac lesions. We report our experience using this technique in surgical excision of left atrial myxoma in 3 patients. METHODS: From November 1995 to March 1997, 3 female patients, ages 45 to 80 years (mean, 62.7 years), received emergency operations for excision of left atrial myxoma. These operations were performed through a right anterior submammary minithoracotomy or right parasternal incision with the assistance of endoscopy during femoro-femoral cardiopulmonary bypass. The myocardium was protected by continuous coronary perfusion with fibrillatory arrest or cardioplegic arrest with aortic cross-clamping. RESULTS: All the tumors were excised completely through the right atrial approach. The bypass time was 92 to 148 minutes (mean, 111 minutes). The operation time was 3.2 to 4.4 hours (mean, 3.7 hours). There were no hospital deaths. Follow-up, which ranged from 6 to 19 months (mean, 10.5 months), was complete in all patients. Transthoracic echocardiographic examination showed good ventricular function without any residual tumors. Patients were found to be in New York Heart Association functional class I or II. They were satisfied with the good cosmetic healing of the incision. CONCLUSIONS: Our experience demonstrates that minimal access surgery is a technically feasible, safe, and effective procedure in surgical excision of left atrial myxoma.     

Impairment of left atrial appendage function after spontaneous conversion of atrial flutter

This paper reports a patient in atrial flutter who spontaneously converted to sinus rhythm while undergoing a transesophageal echocardiogram. Atrial appendage flow velocities were noted to be significantly decreased after conversion to sinus rhythm. Spontaneous contrast also developed in the left atrium shortly after conversion. Spontaneous cardioversion may be associated with decreased mechanical activity of the left atrium and appendage, resulting in "stunning." This provides a possible explanation for the occurrence of thromboembolic events in patients without apparent thrombus before cardioversion.     

Cryptosporidiosis among HIV positive intravenous drug users in Malaysia

A study conducted at the Tampin Drug Rehabilitation Center in Malaysia established a high prevalence (23%) of asymptomatic carriers of Cryptosporidium among exposed HIV positive intravenous drug users (IVDUs). A majority of them were young adults and among the ethnic groups, the Malay HIV positive inmates had the highest prevalence of Cryptosporidium infection.     

Use of a four-layer bandage system in the treatment of an i.v. drug abuser with chronic upper extremity ulcerations: a case study

A patient with a ten-year history of heroin abuse presented to a wound healing clinic for treatment of multiple ulcerations to his upper arm. The largest measured 3.5 cm x 1.7 cm. The patient related that these wounds came from his i.v. heroin use. Previous treatments included iodine packed gauze, saline soaked fine mesh gauze, dakins solution, and wet-to-dry dressings; all treatments were unsuccessful. Treatment included cleansing the wound with normal saline, packing the ulcers with a calcium alginate rope, and wrapping the arm using a four-layer bandage. The dressing remained in place for 7-day time intervals. During the course of treatment, the patient remained heroin-free. No unscheduled dressing changes occurred, nor did the patient report discomfort with the dressing or during dressing changes. The patient was able to maintain complete range of motion throughout care. Complete healing was noted by day 42. The calcium alginate dressing combined with the 4-layer bandage system has proved successful in treating the patient.