Carlo Lavalle

Long term treatment of pulmonary arterial hypertension with beraprost, an oral prostacyclin analogue

OBJECTIVE To evaluate the effects of one years treatment with beraprost, an orally active prostacyclin analogue, in patients with severe pulmonary hypertension. PATIENTS 13 patients with severe pulmonary hypertension. This was primary in nine, thromboembolic in three, and caused by Eisenmenger syndrome in one. METHODS All patients underwent right heart catheterisation. Mean (SD) right atrial pressure was 5 (3) mm Hg, mean pulmonary artery pressure was 48 (12) mm Hg, cardiac index was 2.6 (0.8) l/min/m2, and mixed venous oxygen saturation was 68 (7)%. Beraprost was started at the dose of 20 μg three to four times a day (1 μg/kg/day), increasing after one month to 40 μg three to four times a day (2 μg/kg/day), with further increases of 20 μg three to four times a day in case of clinical deterioration. MAIN OUTCOME MEASURES New York Heart Association (NYHA) functional class, exercise capacity measured by distance walked in six minutes, and systolic pulmonary pressure (by echocardiography) were evaluated at baseline, after one months treatment, and then every three months for a year. RESULTS After the first month of treatment, NYHA class decreased from 3.4 (0.7) to 2.9 (0.7) (p < 0.05), the six minute walking distance increased from 213 (64) to 276 (101) m (p < 0.05), and systolic pulmonary artery pressure decreased from 93 (15) to 85 (18) mm Hg (NS). One patient died after 40 days from refractory right heart failure, and another was lost for follow up at six months. The 11 remaining patients had persistent improvements in functional class and exercise capacity and a significant decrease in systolic pulmonary artery pressure in the period from 1–12 months. Side effects were minor. CONCLUSIONS Oral administration of beraprost may result in long lasting clinical and haemodynamic improvements in patients with severe pulmonary hypertension.

Treatment of pulmonary hypertension in patients undergoing cardiac surgery with cardiopulmonary bypass: A randomized, prospective, double-blind study

Objective Pulmonary hypertension can already be present in patients undergoing cardiac surgery or can be exacerbated by cardiopulmonary bypass. Postoperative treatment is still a challenge for physicians. The aim of this study was to evaluate the effects of inhaled prostacyclin (iPGI2) and nitric oxide (iNO) compared with those of intravenous vasodilators. Methods This prospective, randomized, double-blind study included 58 patients affected by severe mitral valve stenosis and pulmonary hypertension with high pulmonary vascular resistance (> 250 dynes·s·cm−5) and a mean pulmonary artery pressure > 25 mmHg. All patients were monitored by central venous, radial arterial and Swan–Ganz catheters. Data were recorded at six different time points, before induction of anaesthesia, during and after surgery. Prostacyclin and nitric oxide were administered by inhalation 5 min before weaning from cardiopulmonary bypass and continued in the intensive care unit. Right ventricular function was evaluated by transoesophageal echocardiography. Results Hospital mortality was 3.4%. After drug administration, the mean pulmonary artery pressure and pulmonary vascular resistance were significantly decreased in the iNO and iPGI2 groups with respect to the baseline values (P < 0.05) and such a decrease was maintained throughout the study; this was not observed in the control group. In the iNO and iPGI2 groups we demonstrated a significant increase in cardiac indices and right ventricular ejection fraction after drug administration with respect to baseline. Furthermore, patients in the inhaled drug groups were weaned easily from cardiopulmonary bypass (P = 0.04) and had a shorter intubation time (P = 0.03) and intensive care unit stay (P = 0.02) than the control group. Conclusions Our data suggest that both iNO and iPGI2 are effective in the treatment of pulmonary hypertension. iPGI2 has a number of advantages over iNO, including its easy administration and lower cost. Intravenous vasodilator treatment, on the other hand, is effective in terms of mortality but has a higher morbidity rate.

Propagation of the Sinus Impulse Into the Koch Triangle and Localization, Timing, and Origin of the Multicomponent Potentials Recorded in This Area

Background— The presence of a conduction block at the level of the Koch triangle (KT) and the origin of the multicomponent potentials inside this area are controversial issues. We investigated the propagation of the sinus impulse into the KT and the characteristics of multicomponent potentials recorded in that area in patients with and without atrioventricular nodal reentrant tachycardia (AVNRT). Methods and Results— Thirty-two patients (16 with AVNRT, 16 without AVNRT) underwent a sinus rhythm electroanatomic mapping of the right atrium (RA). Conduction velocities in the RA and in the KT were evaluated quantitatively on activation maps and qualitatively on isochronal and propagation maps. The presence, location, and timing of different types of multicomponent potentials were evaluated. A mean of 149±44 points were sampled in the RA, whereas a mean of 79±21 points were collected inside the KT. Propagation block at the level of crista terminalis was not found in any patient, whereas slow conduction inside the KT was found in all (median conduction velocity, 122 cm/s [110 to 135 cm/s] outside KT versus 60 cm/s [48 to 75 cm/s] inside KT; P<0.0001). Jackman potentials were identified inside KT in almost all the patients and were invariably found on the line of collision between the wavefronts activating the KT in opposite directions. Conclusions— No conduction block was detected inside the KT in patients with and without AVNRT. Conduction slowing was demonstrated during propagation of the sinus impulse inside the KT. The genesis of the Jackman potential may be related to the collision of the wavefronts activating KT in opposite directions.

[Defibrillator implantation associated with ventricular arrhythmia ablation: an emerging hybrid approach].

Ventricular arrhythmias are an important cause of morbidity and mortality and are the leading cause of sudden cardiac death. Although implantable cardioverter-defibrillators (ICD) proved to be effective in reducing both sudden cardiac death and all-cause mortality, the ideal therapy remains to be defined because ICD implantation allows to interrupt life-threatening ventricular arrhythmias but does not prevent them. ICD interventions, in terms of shock delivery and antitachycardia pacing, are often associated with invalidating symptoms, such as chest pain, sensation of rapid heartbeat and syncope, and may cause depression in many patients. Both appropriate and inappropriate shocks have been shown to be associated with a worse prognosis. Transcatheter ablation proved to be safe and effective in reducing arrhythmia relapse in patients who experience multiple ICD interventions or electrical storm. In the latter patient subset, ablation often represents the only possibility of interrupting such dramatic events. Ablation has also been evaluated in patients implanted with an ICD in secondary prevention, before device intervention. To date, transcatheter ablation represents an optimal opportunity, complementary to ICD, in the treatment of patients at high risk for sudden death and episodes of ventricular arrhythmias.

Noncompacted ventricular myocardium: characterization by intracardiac echo.

We report a patient with clinical manifestation of arrhythmias and evidence of noncompacted myocardium in both left and right ventricular apex. The diagnosis was made with intracardiac echo performed during the electrophysiologic study. This method has allowed the diagnosis of noncompaction of the ventricular myocardium due to its high resolution. Color Doppler showed trabecular recesses in communication with the ventricular cavity that could not be identified with transthoracic echocardiography.

Intracardiac echocardiography and electroanatomic mapping in diagnosis of arrhythmogenic right ventricular dysplasia.

A 48-year-old man with an episode of syncope and family history of sudden cardiac death was evaluated. The ECG showed negative T waves from V1 to V3 with evidence of epsilon-wave. Magnetic resonance imaging showed replacement with fibrofatty tissue in midapical regions of free wall of the right ventricle with dyskinesia. Transthoracic echocardiography revealed only mild enlargement of the middle right ventricular cavity. A programmed ventricular stimulation induced only an unsustained monomorphic ventricular tachycardia. Intracardiac echocardiography showed mild right ventricular enlargement and outflow dilatation (26 mm), microaneurysms with systolic bulging along the apical segment of the right ventricle. Bipolar voltage mapping, performed by the Carto system, detected a circumscribed low potential (<1.5 mV) area at the same level of the right ventricular apex. Cardiovascular imaging improves the detection of abnormal myocardial areas. Further studies are warranted to support this hypothesis.