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Skin ulcers are a dangerous and uncommon complication of vasculitis. We describe the case of a teenager suffering from Systemic Lupus Erythematosus with digital ulcer resistant to conventional therapy, treated successfully with Hyperbaric Oxygen Therapy. The application of hyperbaric oxygen, which is used for the treatment of ischemic ulcers, is an effective and safe therapeutic option in patients with ischemic vasculitic ulcers in combination with immunosuppressive drugs. Further studies are needed to evaluate its role as primary therapy for this group of patients.

Heart failure patients may frequently undergo repeat hospitalizations, and for this reason recent guidelines recommend a multidisciplinary approach including remote clinical state management through systems such as electronic devices, portable or implantable, with the aim of simplifying patient management and optimizing healthcare resources. This different way of healthcare organization has brought about new levels of responsibility, including device manufacturers responsible for the technical aspects, healthcare facilities responsible for the information systems used for patient clinical data transmission and for ambulatory patient access, and in particular the clinicians who should ensure the process supervision by providing prompt medical assistance if alarm signals are received. The use of telemedicine, however, may engender technical problems of varying difficulties. In terms of responsibility, service providers are not liable for damage deriving from technical default, except in the case of willful misconduct or gross negligence. No less important are the legal issues concerning permissions, conflicts of jurisdiction among nations, problems of service inaccessibility, as well as the identification of medical liability in relation to the activity of a multidisciplinary team, besides issues relating to informed consent and privacy protection. In conclusion, risk management with telemedicine may provide more accurate information and better traceability of operators' activity.

The term "electrical storm" (ES) indicates a state of cardiac electrical instability manifested by several episodes of ventricular tachyarrhythmias (VTs) within a short time. In patients with an implantable cardioverter-defibrillator (ICD), ES is best defined as three appropriate VT detections in 24h, treated by antitachycardia pacing, shock or eventually untreated but sustained in a VT monitoring zone. ES seems to have a low immediate mortality (1%) but frequently (50-80%) leads to hospitalization. Antiarrhythmic drugs have been shown to be very effective in treating ES in patients without ICD, whereas in ICD recipients, device programming is probably a key issue to prevent ES. Since sympathetic overreactivity is an important trigger, the risk of shock delivery should be minimized. Antitachycardia pacing can successfully terminate a significant percentage of fast VTs. Important parameters such as the number of VT cycles needed for VT detection can be increased from nominal values to allow spontaneous termination, and safety features that deliver a shock after a programmable time window independent of programming of antitachycardia pacing (sustained rate duration) should be prolonged or disabled. In some cases it may be advisable to turn off the ICD tachy mode to avoid multiple ineffective shocks. Substrate mapping and VT ablation may be useful for the treatment and prevention of ES.

Purpose: Dual-chamber rate-modulated pacing provides haemodynamic benefits compared with ventricular pacing at rest, but it is unclear whether this also holds true during physical exercise in patients with heart failure. This study assessed the haemodynamic response to a walk test during dual-chamber pacing and ventricular pacing in patients with depressed or normal left ventricular (LV) function., Methods: Twelve patients with an LV ejection fraction <50% and 11 patients with an LV ejection fraction >or=50% underwent two randomised 6-min walk tests under dual-chamber rate-modulated pacing and ventricular pacing at a fixed rate of 70 beats/min. All patients had a dual-chamber pacemaker implanted for complete heart block. LV function was monitored by a radionuclide ambulatory system., Results: In patients with depressed LV function, the change from dual-chamber pacing to ventricular pacing induced a decrease in end-systolic volume at the peak of the walk test (P<0.05), with no difference in end-diastolic volume. As a consequence, higher increases in LV ejection fraction (P<0.0001) and stroke volume (P<0.01) were observed during ventricular pacing. No difference in cardiac output was found between the two pacing modes. In patients with normal LV function, the change from dual-chamber pacing to ventricular pacing induced a significant decrease in cardiac output (P<0.005 at rest and P<0.05 at the peak of the walk test)., Conclusion: Compared with dual-chamber rate-modulated pacing, ventricular pacing improves cardiac function and does not affect cardiac output during physical activity in patients with depressed LV function, whereas it impairs cardiac output in those with normal function.

Background: In order to correct the activation, contraction, and relaxation asynchronism, multisite biventricular stimulation has been proposed as a non-pharmacological alternative for the treatment of patients with congestive heart failure (CHF) NYHA class II-III-IV, resistant to maximal drug therapy and with a QRS duration > 120 ms. Fourier analysis appears a feasible technique for the quantitative and non-invasive evaluation of the inter- and intraventricular conduction delays. The aim of our study was to evaluate the usefulness of Fourier analysis when estimating the electromechanical resynchronization in CHF biventricular paced patients and to follow up these patients., Methods: Forty-five male patients (mean age 64 +/- 5 years) with severe drug-refractory CHF, were submitted to radionuclide ventriculography 14 +/- 7 days, 24 and 36 months after the implantation of a biventricular pacemaker, in order to assess left ventricular ejection fraction using Fourier analysis of the right and left ventricular phase images. Each patient was examined during spontaneous sinus rhythm, P-synchronous right ventricle and P-synchronous biventricular pacing., Results: Fourteen days after biventricular pacemaker implantation, QRS duration decreased from 170 +/- 25 to 147 +/- 25 ms (p < 0.01), left ventricular ejection fraction increased from 24 +/- 6 to 31 +/- 9% (p < 0.005), while standard deviation of the left ventricular phase decreased from 53 +/- 6 to 35 +/- 9 degrees (p < 0.0005). Similar results were obtained at 24 and 36 months., Conclusions: Biventricular pacing appears to be associated with shortening of QRS duration and an improvement in NYHA class and left ventricular ejection fraction in CHF patients with inter- and intraventricular conduction delays as assessed at Fourier analysis radionuclide ventriculography.

Background: Transthoracic electrical cardioversion represents the most effective therapy in converting atrial fibrillation (AF) to sinus rhythm. External cardioverter-defibrillators discharge a current with monophasic and most recently biphasic waveforms. Lately, many articles support the superiority of the biphasic waveform over the monophasic one. Moreover, we have the opportunity to use different biphasic waveforms. The aim of this study was to compare the efficacy (success rate and energy delivered) of a monophasic wave and two different biphasic waves, in patients with persistent AF undergoing external electrical cardioversion. The monophasic wave was delivered by a Zoll M series NM PDMA-9, while the so-called "rectilinear" biphasic waveform was used by a Zoll M series PDM-7S and the biphasic truncated exponential wave by a Laerdal Heartstart 4000., Methods: Sixty-four patients with clinical indications to undergo external electrical cardioversion were randomized into three groups. All the groups were homogeneous for almost all characteristics, particularly atrial dimensions, body surface area, and duration of AF and therapy. Eighteen patients underwent external cardioversion with monophasic waveform (group 1), 22 patients were treated with rectilinear biphasic waveform (group II), and 24 patients with biphasic truncated waveform (group III). A cardioversion protocol, providing up to 5 shocks, with incremental energy levels was used. A blood sample was obtained 6 hours later to evaluate myocardial damage due to shock therapy for each patient., Results: Both biphasic devices demonstrated to be more effective than the monophasic one (group I 78%, group II 95%, group III 100%). Moreover, none of them caused any significant myocardial damage, evaluated in terms of cardiac enzyme release. Nonetheless, the biphasic truncated exponential wave demonstrated an efficiency of 10 0% compared to 95 % of the rectilinear one and 78% of the monophasic one, using less energy/patient (873 +/- 101 J group I, 390 +/- 48 J group II, and 280 +/- 42 J group III), at almost the same shock attempts., Conclusions: Biphasic truncated exponential wave seems to be more effective at a lower energy level.

Background: This study focuses the role of heart rate on cardiac output (CO) at rest and during walk test in patients with dual-chamber pacemaker and depressed or normal left ventricular (LV) function., Methods and Results: In nine patients with ejection fraction (EF) <50% (group A) and in seven with EF 50% (group B) haemodynamics were assessed at rest and during three randomized 6-min walk tests at fixed rate of 70, 90, and 110beats.min(-1). All patients had dual-chamber pacemaker implanted for complete heart block. Left ventricular function was monitored by a radionuclide system. In group A, with increasing pacing-rate from 70 to 110beats.min(-1), CO did not change both at rest and during walk, whereas end-systolic volume (ESV) increased (P<0.05) and stroke volume (SV) decreased from 68+/-6 to 47+/-9ml at rest (P<0.0001) and from 112+/-21 to 76+/-17ml during walk (P<0.005). In group B, with increasing pacing-rate, CO rose from 6.4+/-0.7 to 9.1+/-1.6l.min(-1)at rest (P<0.001) and from 10+/-1.5 to 14.1+/-2.2l.min(-1)during walk (P<0.0001), with no change in ESV and SV., Conclusions: Increasing heart rate in presence of ventricular asynchrony induced by dual-chamber pacing has negative effect on cardiac contractility and does not improve CO at rest or during physical activity in patients with depressed LV function as occurs in those with normal function.

Although many studies document oxygen radical formation during ischemia-reperfusion, few address the sources of radicals in vivo or examine radical generation in the context of prolonged ischemia. In particular, the contribution of activated neutrophils remains unclear. To investigate this issue, we developed a methodology to detect radicals without interfering with blood-borne mechanisms of radical generation. Dogs underwent aorta and coronary sinus catheterization. No chemicals were infused; instead, blood was drawn into syringes prefilled with a spin trap and analyzed by electron paramagnetic resonance spectroscopy. After 90 min of coronary artery occlusion, transcardiac concentration of oxygen radicals rose severalfold 10 min after reflow and remained significantly elevated for at least 1 h. Radicals were mostly derived from neutrophils, as shown by marked reduction after the administration of 1) neutrophil NADPH oxidase inhibitors and 2) a monoclonal antibody (R15.7) against neutrophil CD18 adhesion molecule. Reduction of radical generation by R15.7 was also associated with a significantly smaller infarct size and no-reflow areas. Thus our data demonstrate that neutrophils are a major source of oxidants in hearts reperfused in vivo after prolonged ischemia and that antineutrophil interventions can effectively prevent the increase in oxygen radical concentration during reperfusion.

Background: Experimental studies have demonstrated that during stress-induced myocardial ischemia, coronary obstruction and diastolic perfusion time are factors that limit subendocardial perfusion and correlate to degree of myocardial dysfunction. The relation between these two factors has not yet been investigated in humans. The aim of the present study was to assess the relation between diastolic perfusion time and degree of coronary stenosis during different types of stress tests., Methods and Results: Nine patients with isolated and proximal stenosis of the left anterior descending coronary artery were selected. Patients underwent three different randomized stress tests (upright, supine bicycle stress test, and transesophageal atrial pacing). Diastolic perfusion time, heart rate (RR interval), and systolic and diastolic pressures were measured during the test and at the ischemic threshold (0.1-mV ST-segment depression). Angiographic measurements of coronary stenosis were evaluated by quantitative coronary angiography. At the ischemic threshold, significant differences among tests were found in heart rate (P < .05), systolic pressure (P < .001), and diastolic pressure (P < .05). In each stress test, diastolic perfusion time at the ischemic threshold was closely correlated with minimal stenosis diameter (r = .97; P < .001) and percent diameter stenosis (r = .92; P < .001) with no difference among the tests. In contrast, heart rate, rate-pressure product, and time to ischemic threshold were not significantly correlated with percent diameter stenosis and minimal stenosis diameter. No significant correlation was observed at the ischemic threshold between diastolic perfusion time and corresponding values of heart rate, despite the close correlation at rest (r = .95; P < .001)., Conclusions: Despite differences in associated hemodynamic responses to various stress tests, a close relation exists between stenosis severity and diastolic perfusion time at the onset of stress-induced myocardial ischemia. Therefore, diastolic perfusion time at the ischemic threshold may be an indirect estimate of the hemodynamic significance of coronary stenosis.

Low-density lipoproteins (LDL) oxidized by oxygen radicals are a potent atherogenic stimulus. Chemically modified LDL are internalized by macrophages via a specific cell surface receptor that was termed the scavenger receptor, and could induce foam cell transformation. Post-translational nonenzymatic glycosylation of low density lipoprotein (LDL) occurs in vivo in diabetic patients. Glycosylated LDL (glcLDL) is degraded by macrophages in part by the classic LDL-receptor and in part by the scavenger receptor. This latter mechanism may contribute to the formation of foam cells and acceleration of atherosclerosis in diabetes mellitus. Oxygen free radicals (ORs) could induce LDL peroxidation and subsequent formation of foam cells. Glycosylation may alter protein conformation. A free radical is any chemical species that has an unpaired electron. This property renders it highly chemically reactive. When a radical reacts with a non radical another free radical is generated. This characteristic enables radicals to trigger chain reactions. Oxygen radicals are: superoxide anion (.O2-), hydroxyl radical (.OH) and hydrogen peroxide (H2O2). Thus, the aim of this study was to investigate whether glcLDL are susceptible to peroxidative modification by ORs. GlcLDL was prepared incubating LDL with 40 mM glucose in sterile phosphate-buffer-EDTA 1 mM for 10 days at 37 degrees C. Control LDL (cLDL) was similarly incubated with buffer but without glucose. After this preparation both forms of LDL were oxidized by CuSO4 (15 microM for 20 hours at 37 degrees C) or by xanthine/xanthine oxidase (X:2 mM/XO: 100 mU for 20 hours at 37 degrees C).(ABSTRACT TRUNCATED AT 250 WORDS)

Forty patients with coronary artery disease and 15 normal subjects (group C) were studied to assess the influence of the site of stress-induced myocardial ischemia on cardiovascular response after exercise. Patients were divided in 2 groups according to myocardial thallium-201 scintigraphy: those with an anteroseptal reversible perfusion defect (group A; n = 24), and those with an inferoposterior reversible perfusion defect (group I; n = 16). All patients underwent serial bicycle exercise stress tests. The first 2 stress tests were interrupted when 0.1 mV of ST-segment depression was achieved (2,000 to 2,500 kg-m); a third test was stopped before the onset of ischemia (1,500 kg-m). Normal subjects performed stress tests at comparable work loads. At ischemic threshold, there was no difference in ejection fraction between groups A (65.5%) and I (67.3%). Mean values and recovery ratios of heart rate and systolic blood pressure were significantly higher in group A than in C and I during the recovery period of the 2,000 to 2,500 kg-m stress test. In contrast, no significant difference was observed among the groups in the 1,500 kg-m stress test, and between groups I and C in any stress test. The data show that in patients with the same degree of stress-induced impairment of ventricular function, the anterior site of ischemia leads to persistently higher values of heart rate and blood pressure after exercise, which are likely due to an enhanced adrenergic discharge.

Recently, a new class of drugs has been developed with unique properties with regard to cardiovascular pharmacology: K(+)-channel openers. The increased K+ efflux from smooth muscle cells induced by these drugs is accompanied by a reduced intracellular availability of free Ca++, which in turn induces vascular relaxation. This property is currently being exploited to achieve peripheral and coronary artery dilatation in patients with ischemic heart disease. Cromakalim, pinacidil, and nicorandil, are the most extensively investigated agents in this class. Nicorandil, in addition to its K(+)-channel opener property, also shows a nitrate-like activity on guanylate cyclase of vascular smooth muscle cells. Clinical trials demonstrate that chronic administration of nicorandil can significantly increase exercise tolerance in patients with coronary artery disease. In experimental studies, this drug has also shown protective effects against myocardial injury induced by ischemia and reperfusion, by mechanisms partly independent of its vasodilating properties. These results suggest that K(+)-channel openers may have a relevant place in the pharmacological treatment of patients with ischemic heart disease.

The relationship between either heart rate or diastolic time and ST segment depression has been evaluated during supine and upright exercise in 16 coronary artery disease patients. Diastolic perfusion time and ST segment depression were related by a linear regression, which was independent of exercise posture. The entity of ST segment depression was greater during supine than in upright exercise for the same heart rate. The assessment of the relationship between heart rate and diastolic perfusion time during two exercises showed that at the same heart rate, diastolic perfusion time was shorter in supine posture. In conclusion, the greater entity of ST segment depression induced by supine rather than upright exercise might be explained by the effect of supine posture on diastolic perfusion time.

The patients with so-called syndrome X experience true myocardial ischaemia in spite of their anatomically normal coronary arteries. The pathogenetic mechanism of the effort-induced ischaemia in these patients should be obviously different from that of patients with atherosclerotic coronary artery lesions. An inadequate coronary dilatory capacity in response to increased oxygen demand has been proposed as mechanism responsible of ischaemic response to effort (Canon et al., 1983; Canon et al., 1985). Since diastolic duration expressed as percentage of the cardiac cycle has implications with the myocardial oxygen demand/supply ratio (Boudoulas et al., 1982; Maseri et al., 1977), the purpose of this study has been to evaluate the behaviour of this parameter at the outcome of the ischaemic electrocardiographic changes during stress testing in the patients with syndrome X.

The present study has been performed to assess the effects of alinidine on diastolic duration during exercise in chronic coronary artery disease. Twelve male patients with stable effort angina and without previous myocardial infarction were studied. They received alinidine or placebo in a double-blind randomized crossover trial for 3 days after a wash-out period of 4 days. Alinidine was administered at a dosage of 30 mg 3 times a day. At the end of each treatment the patients underwent upright bicycle exercise. Left ventricular time intervals were obtained by means of carotid thermistor plethysmography. Diastolic duration was calculated by subtracting the electromechanical systole from the R-R interval and expressed as a percentage of the cardiac cycle (%D). Alinidine increased both total exercise duration from 246.7 +/- 120.7 to 346.6 +/- 114.1 s (p less than 0.05) and time to 0.1-mV ST segment depression from 98.3 +/- 53 to 187.2 +/- 105 s (p less than 0.05). Similarly the drug induced a reduction of the rate-pressure product and of the extent of ischemic ST segment depression during exercise. %D was increased by alinidine both at rest and during exercise. A direct linear regression between R-R and %D was found after both alinidine and placebo treatments either at rest or during exercise. Nevertheless, no difference was observed between both slopes and intercepts. Therefore, since the relationship between R-R interval and %D was unaffected by alinidine, it was possible to hypothesize that the changes in diastolic duration were due only to the bradycardic action of the drug.