Comparison of permanent cardiac pacing and cardiac pacing on demand in mixed carotid sinus syndrome. Acute- and medium-term follow-up study

The aim of the study was to evaluate the importance of atrial synchronism for pacing therapy of patients with mixed carotid sinus syndrome. On 23 patients (21 m, 2 f; mean age 69 +/- 8 years) affected by symptomatic mixed carotid sinus syndrome we performed: 1) the study of ventriculo-atrial conduction, 2) the evaluation of pacemaker effect and 3) the carotid sinus massage in standing position during VVI and DVI temporary pacing. All patients received a permanent DVI pacemaker and then underwent a two-month period single-blind, randomized, cross-over study on DVI vs VVI mode. During DVI period, no syncope occurred in any patients, minor symptoms persisted in 11 (48%) of them; during VVI period syncopes recurred in 3 patients, symptoms requiring the withdrawal of VVI pacing and premature DVI reprogramming in 8, minor symptoms were observed in 17 (74%). A comparison between 14 patients who preferred DVI period (Group A) and the remaining 9 patients who had no preference for DVI and VVI period (Group B) revealed that Group A patients had a greater pacemaker effect (-34 +/- 16 mmHg vs -16 +/- 14 mmHg; p less than 0.02) and a higher prevalence of ventriculo-atrial conduction (78% vs 44%; p = 0.1), while the entity of the systolic pressure fall caused by carotid sinus massage was similar in the two groups both during VVI mode (Group A -51 +/- 16 mmHg vs Group B -56 +/- 27 mmHg) and DVI mode (Group A -38 +/- 17 mmHg vs Group B -45 +/- 17 mmHg).(ABSTRACT TRUNCATED AT 250 WORDS)     

Neurally mediated syncope detected by carotid sinus massage and head-up tilt test in sick sinus syndrome

It is generally accepted that a positive response to carotid sinus massage (CSM) or head-up tilt (HUT) in patients affected by syncope suggests a reflex cause of the syncope. To study the role of the autonomic nervous system in causing syncope in the sick sinus syndrome (SSS), CSM and HUT were performed in 35 consecutive patients (20 men, mean age 70 +/- 9 years) with syncope and SSS. Results were compared with those in 35 patients affected by syncope that, despite careful cardiovascular and neurologic examination, were of uncertain origin (21 men; mean age 68 +/- 9 years) and with those of 35 subjects without syncope (20 men; mean age 69 +/- 10). All patients underwent CSM in the supine and standing positions for 10 seconds and HUT to 60 degrees for 60 minutes. In the patients with SSS, the full reproduction of spontaneous symptoms by CSM occurred in 21 (60%) and by HUT, in 19 (54%). At least 1 test was positive in 28 patients (80%): cardioinhibitory or mixed responses in 69%, vasodepressor responses in 11%. The percentages of positive tests in the patients with syncope of uncertain origin were similar to or slightly less than those of patients with SSS (CSM 63%, HUT 26%, overall 74%) with cardioinhibitory or mixed responses in 54% and vasodepressor in 20% (p less than 0.05). In control subjects, syncope was induced by CSM in 1 (3%) and by HUT in 2 (6%); overall positivity was 9%. In conclusion, in most patients affected by syncope and SSS, an abnormal neural reflex probably plays a major role in causing syncope.(ABSTRACT TRUNCATED AT 250 WORDS)     

The spectrum of cardiovascular abnormalities in autosomal dominant polycystic kidney disease: a 10-year follow-up in a five-generation kindred.

Clinical, electrocardiographic and echocardiographic data were collected in a group of 228 patients with autosomal dominant polycystic kidney disease (PKD) and in another group of 146 unaffected members (NPKD) both comprised in a five-generation kindred followed for 10 years, in order to determine the profile and prevalence of cardiovascular derangement of the genetic disease. A family of 181 members was used as a control. The prevalence of left ventricular hypertrophy in the three groups was 24, 14 and 6% respectively (p less than 0.01); after 10 years it increased up to 35, 26 and 13% respectively (p less than 0.05). The evidence of mitral-valve prolapse was more frequent in PKD and in NPKD group (25 and 20% respectively) than in control subjects (2%) (p less than 0.0001). Mitral incompetence was found in 30, 18 and 8% of those groups respectively (p less than 0.002). The large difference in mitral involvement did not change over time. Tricuspid valve prolapse was detected in 5, 4 and 1% of the three groups, respectively (p less than 0.05). A small increase in frequency was found after 10 years only in polycystic kidney disease patients. Regurgitant aortic lesions were present in higher prevalence in PKD (19%) and NPKD (17%) members than in controls (5%) (p less than 0.001). After 10 years they were 23, 20 and 8%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

Study on tissue concentrations of antibiotics: bacampicillin in gingiva and maxillary bones

21 patients, whose age ranged from 17 to 60 years and who had not been previously treated with antibiotics or other drugs, received bacampicillin as a perioperative prophylaxis for minor operations in the oral cavity. Four oral doses of bacampicillin were administered: each dose of 800 mg every 12 h, and the last dose was administered 2 h before surgery. To assess bacampicillin serum concentrations two blood samples were collected from each patient: the first sample was obtained 1 h before surgery and the second one during surgery. Together with the second blood sample, small quantities of gingiva and bone were obtained from each patient to also assess the antibiotic concentrations in these tissues (microbiological method). The results show that bacampicillin reaches high concentrations in both the blood and tissues studied by us, and that a direct correspondence exists between blood and gingival and bone tissue concentrations. Furthermore, it should be noted that no postoperative infections developed in our patients. These results lead to the conclusion that bacampicillin appears to be a suitable drug in the therapy of dental infections.     

Perforated jejunal diverticulitis: personal experience and diagnostic with therapeutical considerations

A case of perforated jejunal diverticulitis in a 87-year-old man is described and the literature is reviewed. Jejunal diverticulosis (JD) is estimated to occur in 0.02% to 1.3% of the adult population and is found most often in the elderly. The acute diverticulitis with perforation has been reported as high as 2.3% among patients with JD and is associated with high mortality. Clinical presentation mimic other more common acute intraperitoneal inflammatory conditions. Enteroclysis and abdominal CT are the most specific diagnostic tests. The common treatment is surgical resection of the involved segment. Laparoscopic resection and medical and medical/radiological approaches have also been proposed. Diagnostic and therapeutical aspects of this pathology are discussed.     

IgM monoclonal gammopathy–associated neuropathies with different IgM specificity

Background and purpose: Antibodies directed against myelin‐associated glycoprotein (MAG) are believed to be the most frequent biologic marker of the neuropathies associated with IgM monoclonal gammopathy of undetermined significance (MGUS). The objective of this study was to examine the prevalence of antiganglioside and/or sulfatide‐positive patients and their clinical findings, including therapeutic response, compared to anti‐MAG‐positive or seronegative patients. Methods: We prospectively followed 46 patients with MGUS who were diagnosed in our tertiary referral centers for polyneuropathy since 1997. All patients underwent nerve conduction studies and were tested for anti‐MAG, gangliosides, and sulfatide antibodies. All the anagraphic and clinical data (including symptoms, disability scale, therapy, secondary malignancy development) were recorded in a database and compared between three patients’ groups (anti‐MAG‐positive; antiganglioside/sulfatide‐positive; no reactivity). Results: Anti‐MAG reactivity was present in 17 (37%) patients; other 17 patients (37%) had antiganglioside/sulfatide reactivity and 12 (26%) had no reactivity. Patients with antiganglioside/sulfatide positivity, although heterogeneous by a clinical and neurophysiological point of view, had the most severe neuropathic manifestations and a higher disability score at nadir (P < 0.001). These patients had a better response to both intravenous immunoglobulin therapy and rituximab. Conclusions: Our results suggest that antiganglioside/sulfatide‐positive patients form a relevant portion of patients with MGUS‐associated polyneuropathy seen in tertiary care centers and should be considered in future studies on treatment response.     

Expression of fibrinogen receptors during activation and subsequent desensitization of human platelets by epinephrine

Epinephrine causes platelet aggregation and secretion by interacting with alpha 2-adrenergic receptors on the platelet surface. Platelet aggregation requires the binding of fibrinogen to a specific receptor on the membrane glycoprotein IIb-IIIa complex. Although the IIb-IIIa complex is identifiable on the surface of resting platelets, the fibrinogen receptor is expressed only after platelet activation. The current studies were designed to examine the effect of occupancy of platelet alpha 2-adrenergic receptors by epinephrine on the expression of fibrinogen receptors and on the aggregation of platelets. The ability of epinephrine to induce the expression of fibrinogen receptors was studied under two different conditions: acute stimulation (less than 1 min) and prolonged stimulation (50 to 90 min), the latter of which is associated with a reduction or "desensitization" of the platelet aggregation response. Expression of the fibrinogen receptor was monitored with 125I-fibrinogen as well as with 125I-PAC-1 (PAC-1), a monoclonal antibody that binds to the glycoprotein IIb-IIIa complex only after platelets are activated. Epinephrine caused an immediate increase in PAC-1 and fibrinogen binding that was dependent on occupancy of the alpha 2-receptor by epinephrine and on the presence of extracellular free Ca (KCa = 30 mumol/L). By itself, 1 mmol/L Mg was unable to support induction of the fibrinogen receptor by epinephrine. However, it did decrease the Ca requirement by about two orders of magnitude. Prolonged stimulation of unstirred platelets by epinephrine led to a 70% decrease in the aggregation response when the platelets were subsequently stirred. Despite their decreased aggregation response, desensitized platelets bound PAC-1 and fibrinogen normally, indicating that the loss of aggregation was not due simply to a decrease in fibrinogen receptor expression. Although desensitization was not affected by pretreatment of the platelets with aspirin, it was partially prevented when extracellular Ca was chelated by EDTA during the long incubation with epinephrine. These studies demonstrate that once platelet alpha 2-adrenergic receptors are occupied by epinephrine, extracellular Ca is involved in initiating the aggregation response by supporting the induction of the fibrinogen receptor and the binding of fibrinogen. Furthermore. Ca-dependent reactions subsequent to fibrinogen binding may be necessary for maximal platelet aggregation and are impaired when platelets become desensitized to epinephrine.     

Chlorambucil therapy in hairy cell leukemia: effects on lipid composition and lymphocyte subpopulations

Two patients with progressive hairy cell leukemia following splenectomy were treated with low-dose daily chlorambucil. Both had an objective hematologic response as determined by a return to normal hematocrit and platelet count. This was also reflected in the mononuclear cell fraction by the normalization of cholesterol content, cholesterol/phospholipid ratio, and the lymphocyte subpopulations. This article confirms previous reports on the efficacy of chlorambucil in this setting and describes some morphological, and biochemical concomitant events.