Internal Cardioversion of Chronic Atrial Fibrillation in Patients

Transvenous internal cardioversion of chronic AF using a right atrium (RA) coronary sinus (CS) vector requires more energy than cardioversion of paroxysmal AF. Chronic AF is not terminated in 25% of patients using biphasic shocks up to 10 J. We therefore evaluated efficacy, safety, and tolerability of internal cardioversion using a "unipolar' configuration (RA to skin patch) and biphasic shocks in patients with long-lasting AF and different heart disease. In each patient, biphasic R have synchronous shocks were delivered between a large defibrillating surface area electrode in the RA and a skin patch in the left prepectoral position. Defibrillation protocol started with a test shock of 0.4 J. Shocks were repeated and increased until termination of AF or a maximum of 34 J. Sedation was used when the patient described the shock as painful. This study included 11 patients with a mean age of 67 ± 8 years (range 56–83). AF duration was ± 1 month in all patients with a mean duration of 11 ± 11 months (range 2–36). Underlying heart disease was present in all patients and the mean left atrial dimension was 43 ± 9 mm (range 26–57). AF was terminated in 10 of 11 patients (91 %) with a mean delivered energy of the successful shocks of 18.7 ± 8.7 J (median energy 16.9 J; range 7.3–32.5) and a mean leading edge voltage of 564 ± 129 V. The mean shock impedance at the defibrillation threshold was 71 ± 13 Ω, (range 59–103). A total of 131 shocks were delivered without any complication and proarrhythmia episodes. We conclude that low energy "unipolar" internal cardioversion is a simple, safe, and effective technique for termination of chronic AF in patients with heart disease. The procedure is often tolerated under light sedation.     

Transthoracic Sensor for Noninvasive Assessment of Left Ventricular Contractility: Validation in A Minipig Model of Chronic Heart Failure

Background: Invasively measured left ventricular (LV) dP/dt is the accepted standard for measuring acute and chronic directional changes in LV contractility. Recently, we developed a noninvasive force sensor based on an accelerometer positioned on the chest, which measures the vibrations generated by isovolumic myocardial contraction. The aim of this paper was to compare noninvasive (accelerometer) versus invasive (LV dP/dt) indices of myocardial contractility in a chronic minipig model of pacing‐induced heart failure (HF). Comparative assessment was performed both at rest and following dobutamine infusion. Methods: In adult male minipigs (n = 6), LV contractility was simultaneously assessed both invasively (LV dP/dt, Millar catheter) and noninvasively (accelerometer) at rest and following dobutamine (up to 7.5 mcg/kg/min), both before and after development of HF by pacing the LV at 180 beats/min for 3 weeks. Results: Invasive and noninvasive assessments were obtained in 24 conditions (12 at rest and 12 after dobutamine infusion). Sensor‐based cardiac force changes were significantly related to positive peak LV dP/dt_max changes following dobutamine infusion both in normal (r = 0.88, P < 0.001) and failing heart (r = 0.89, P < 0.001). The force‐frequency relation showed a tight correlation between invasive and noninvasive assessment (r = 0.68, P = 0.02). Conclusions: The force‐frequency relation can be assessed noninvasively by a transthoracic sensor based on an accelerometer. The method can efficiently detect the development of resting dysfunction and the contractile reserve at different HF steps, with potential for wearable HF monitoring. (PACE 2010; 795–803)     

Analysis of the Action of Corticosteroid Treatment in Immunologic Infertility: A Preliminary Report and an Alternative Hypothesis

ABSTRACT: The presence of sperm antibodies can be demonstrated in 8–10% of the male partners of infertile couples. The therapeutic schedule with which the highest pregnancy rate has been obtained in these cases is that proposed by Shulman, which uses methylprednisolone (MP). If treatment with corticosteroids (CS) is effective, the way in which it acts is not entirely clear. In this study we report the results of 16 treatment cycles with CS administered to eight male patients having sperm antibodies in their serum, in which several parameters of humoral immunity were evaluated. The results are conflicting: several parameters (such as IgG concentration) underwent only slight variations after 7 days of therapy, whereas in 12 cycles out of 16, the Tray agglutination test (TAT) indicated that a reduction or disappearance of the antibodies had been obtained. This confirms the usefulness of CS in immunological infertility, and allows us to hypothesize that the beneficial effect may be found in a reduction of inflammation rather than in a suppression of the immunological response, since CS are well known to have these two kinds of effect.     

Muscle fatigue,nNOS and muscle fiber atrophy in limb girdle muscular dystrophy

Muscle fatigability and atrophy are frequent clinical signs in limb girdle muscular dystrophy (LGMD), but their pathogenetic mechanisms are still poorly understood.We review a series of different factors that may be connected in causing fatigue and atrophy, particularly considering the role of neuronal nitric oxide synthase (nNOS) and additional factors such as gender in different forms of LGMD (both recessive and dominant) underlying different pathogenetic mechanisms.In sarcoglycanopathies, the sarcolemmal nNOS reactivity varied from absent to reduced, depending on the residual level of sarcoglycan complex: in cases with complete sarcoglycan complex deficiency (mostly in beta-sarcoglycanopathy), the sarcolemmal nNOS reaction was absent and it was always associated with early severe clinical phenotype and cardiomyopathy.Calpainopathy, dysferlinopathy, and caveolinopathy present gradual onset of fatigability and had normal sarcolemmal nNOS reactivity. Notably, as compared with caveolinopathy and sarcoglycanopathies, calpainopathy and dysferlinopathy showed a higher degree of muscle fiber atrophy.Males with calpainopathy and dysferlinopathy showed significantly higher fiber atrophy than control males, whereas female patients have similar values than female controls, suggesting a gender difference in muscle fiber atrophy with a relative protection in females. In female patients, the smaller initial muscle fiber size associated to endocrine factors and less physical effort might attenuate gender-specific muscle loss and atrophy.Key words: LGMD, nNOS, sarcoglycan     

Ropivacaine in paediatric surgery: preliminary results

In a double blind study 40 patients, aged 1–9 years, undergoing elective minor surgery were examined and randomly divided in two groups (20 children each). After light general anaesthesia Group 1 received caudal injection of bupivacaine 0.25% 2 mg·kg^?1 while Group 2 received 0.2% ropivacaine 2 mg·kg^?1. No differences were observed in demographic data, HR, BP and duration of surgery; the onset time of anaesthesia was 12 min and 9 min in Group 1 and 2 respectively. Ten patients in Group 1 received paracetamol in the first 24 h after surgery while only two children in Group 2 needed analgesic; even the duration of analgesia in the patients requiring paracetamol was superior in group 2 (520 min vs 253 min). No motor block was apparent at awakening in either group and no side effect was noticed. In conclusion ropivacaine seems to be an effective and safe drug in paediatric regional anaesthesia.