Use of the Implantable Loop Recorder in Evaluation of Patients with Unexplained Syncope

Syncope is a complex symptom with multiple potential etiologies that can be difficult to establish. The major obstacles to diagnosis are the periodic and unpredictable nature of events and the high spontaneous remission rate. Short-term ECG monitoring often is unproductive when initial noninvasive testing is negative due to the low probability of recurrence during the brief monitoring period. Implantable loop recorders extend the ability to monitor cardiac patients, enhancing the diagnostic yield to as high as 85% in difficult to diagnose syncope. Several recent studies suggest that prolonged monitoring with an implantable loop recorder has a role in patients with syncope and conduction disturbances, negative tilt testing, and unexplained seizures, and may be superior to conventional testing with tilt and electrophysiologic studies. (J Cardiovasc Electrophysiol, Vol. 14, pp. S70-S73, September 2003, Suppl.)     

Atrial Support Pacing in Heart Failure: Results from the Multicenter PEGASUS CRT Trial

Atrial Pacing in Heart Failure. Introduction: Cardiac resynchronization therapy (CRT) efficacy trials to date used atrial‐synchronous biventricular pacing wherein there is no or minimal atrial pacing. However, bradycardia and chronotropic incompetence are common in this patient population. This trial was designed to evaluate the effect of atrial support pacing among heart failure patients receiving a CRT defibrillator. Methods and Results: PEGASUS CRT was a multicenter, 3‐arm, randomized study. At 6 weeks, patients were randomized to DDD mode at a lower rate of 40 bpm (DDD‐40; control arm), or one of the following 2 treatment arms: DDD‐70, or DDDR‐40. The primary endpoint was a clinical composite endpoint that included all‐cause mortality, heart failure events, NYHA functional class, and patient global self‐assessment. Subjects were classified as improved, unchanged, or worsened at 12 months. There were 1,433 patients randomized, of whom 66% were male, mean age was 67 ± 11 years, and mean left ventricular ejection fraction was 23 ± 7%. The average follow‐up time was 10.5 ± 3.5 months and 1,309 patients contributed to the primary endpoint. No significant differences were observed in the composite endpoint between either of the 2 treatment arms compared to the control arm (P>0.05 for both comparisons). Additionally, there were no differences among the groups in mortality or heart failure events. Conclusion: In advanced heart failure patients treated with CRT, atrial support pacing did not improve clinical outcomes compared to atrial tracking. However, atrial pacing did not adversely affect mortality or heart failure events. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1317‐1325, December 2012)     

A comparison of emergence delirium scales following general anesthesia in children

Background: Emergence delirium (ED) is of increasing interest since the introduction of short‐acting volatiles such as sevoflurane. Methods: We compared the Pediatric Anesthesia Emergence Delirium (PAED), Watcha and Cravero scales for assessing the presence of ED in 117 of 118 consecutive children <18 years recovering from general anesthesia. The primary measure was the worst score for ED as assessed on each scale and for each patient during their PACU stay. An experienced anesthetist observer also made a subjective assessment of the presence of ED. Results: A PAED score of ≥10 detected ED in 37 children (32%), while the Watcha detected 30 (26%) and Cravero 41 (35%). Twenty‐five patients (21%) fulfilled criteria for ED in all three scales as did all eight patients assessed by the experienced pediatric anesthetist observer. Median PAED scores (interquartile ranges) for patients assessed as having ED or not respectively were for Watcha, 12 (11,14), 7 (4,8); for Cravero, 11 (9,13), 7 (4,8); and for the experienced anesthetist observer, 14.5 (13.5,16.5), 7 (6,10). Conclusions: All three scales correlated reasonably well with each other but have individual limitations in their potential to assess whether ED is present. In the absence of developing an improved research tool to assess ED, a PAED score >12 appears to provide greater sensitivity and specificity than a PAED score ≥10. However, the Watcha scale is a simpler tool to use in clinical practice and may have a higher overall sensitivity and specificity than the other scales.     

Urinary oestrogen levels and follicle ultrasound measurements in clomiphene induced cycles with an endogenous luteinizing hormone surge

Summary. Total oestrogen in urine and the ultrasonic size of the follicles were measured in relation to the onset of the endogenous luteinizing hormone (LH) surge (day 0) in 18 cycles induced with clomiphene citrate in an in-vitro fertilization programme. Oestrogen values in urine (μg/24 h) increased progressively during the late follicular phase up to the day of the onset of the surge. The mean maximum follicle diameter (22·3, SD 4·7 mm) estimated by ultrasound was measured on day 0. At the onset of the LH surge, the values of urinary total oestrogen showed a better relation with the total volume of the first three follicles in order estimated by ultrasound ( r = 0·71) than with the mean ultrasonic diameter of the leading follicle ( r = 0·56). A wide range of individual values for both urinary oestrogen and follicle size was found. In another group of 32 women treated with clomiphene for recovery of oocytes used for research purposes, a good correlation was found between the mean ultrasonic follicle diameter 16 h before the laparoscopy and the follicle diameter calculated from the fluid volume at aspiration ( r = 0·80). These results suggest that the decision when to give human chorionic gonadotrophin (hCG) in an in-vitro fertilization programme remains arbitrary in many individual cases. Apart from the oestrogen levels, the calculation of the size of all follicles, instead of only the leading one, may give further help in timing the hCG.     

Aetiology of non-immune hydrops: the value of echocardiography

Summary. Forty-eight pregnancies, five of them multiple, were referred for fetal cardiac assessment following the detection of non-immune hydrops fetalis; there were 52 hydropic fetuses in total. A cardiovascular aetiology was found in 21 of these 52 (40%); structural heart disease was present in 13, tachyarrhythmia in the remaining eight. The accurate delineation of these causes was possible using fetal echo-cardiography, and enabled rational management to be instituted. This included termination of pregnancy, pharmacological control of arrhythmias and appropriate timing of delivery.     

The response of asthmatic children to the heated nebulization of Salbutamol

The effect of a nebulized solution of Salbutamol heated to 37°C was compared with that of Salbutamol nebulized in the standard manner. Forty asthmatic children were assigned randomly to a heated or standard nebulization. Each child received randomly either half or the full recommended dose of Salbutamol on separate occasions. No untoward side effects were observed. Baseline measurements of peak exploratory flow rate (PEFR), forced vital capacity (FVC) and 1 s forced expiratory volume (FEV₁) were not significantly different among the groups. There was no statistically significant difference among the groups when assessed 15 min after treatment, indicating that neither a change in temperature nor in dose had any significant effect on response at this time. It is concluded that at the dosages used there is no advantage in heating nebulized Salbutamol to 37°C. The equipotent effect of half the recommended dose of Salbutamol at both temperatures suggests that the recommended dose of Salbutamol is too high and that the lowest optimal dose needs to be ascertained.     

TREATMENT OF CYSTINOSIS WITH A DIET POOR IN CYSTINE AND METHIONINE

Two siblings with cystinosis are presented. Case 1, a 16-month-old boy, presented with a severe renal tubular insufficiency. Case 2, a 7-year-old girl, was a dwarf with both glomerular and tubular renal insufficiency. Case 1 was initially treated with high doses of vitamin D₂ and electrolyte supplements for more than 2 months without significant alteration of the condition. Thereafter he was treated for 23 days with 150 mg penicillamine per day again without any significant clinical or biochemical improvement. Both patients were then followed through 1 year on treatment with a diet poor in cystine and methionine supplemented with cholinechloride, an anabolic steroid, high doses of vitamin D₂, electrolytes, oral iron and a combined vitamin preparation. After some time there was considerable difficulty in giving the patients sufficient amounts of the diet, consequently the diet had to be modified with supplement of cow's milk. On this treatment case 1 attained a distinct clinical improvement with healed rickets and normal growth. There was no evidence of mobilisation of the stored cystine. Case 2 obtained a healing of the rickets and some gain in height during the treatment, but otherwise the general condition was unaltered, and she continued to have increasing renal glomerular insufficiency.