Furio Colivicchi

Permanent Cardiac Pacing Versus Medical Treatment for the Prevention of Recurrent Vasovagal Syncope A Multicenter, Randomized, Controlled Trial

Background—This clinical investigation was performed to compare the effects of permanent dual-chamber cardiac pacing with pharmacological therapy in patients with recurrent vasovagal syncope. Methods and Results—Patients from 14 centers were randomized to receive either a DDD pacemaker provided with rate-drop response function or the &bgr;-blocker atenolol at the dosage of 100 mg once a day. Inclusion criteria were age >35 years, ≥3 syncopal spells in the preceding 2 years, and positive response to tilt table testing with syncope occurring in association with relative bradycardia. The primary outcome was the first recurrence of syncope after randomization. Enrollment was started in December 1997, and the first formal interim analysis was performed on July 30, 2000. By that time, 93 patients (38 men and 55 women; mean age, 58.1±14.3 years) had been enrolled and randomized, although follow-up data were available for all patients (46 patients in the pacemaker arm, 47 patients in the pharmacological arm). The interim analysis showed a significant effect in favor of permanent cardiac pacing (recurrence of syncope in 2 patients [4.3%] after a median of 390 days) compared with medical treatment (recurrence of syncope in 12 patients [25.5%] after a median of 135 days; OR, 0.133; 95% CI, 0.028 to 0.632;P =0.004). Consequently, enrollment and follow-up were terminated. Conclusions—DDD pacing with rate-drop response function is more effective than &bgr;-blockade for the prevention of syncopal recurrences in highly symptomatic vasovagal fainters with relative bradycardia during tilt-induced syncope.

Head-up tilt testing potentiated with low-dose sublingual isosorbide dinitrate : a simplified time-saving approach for the evaluation of unexplained syncope

BACKGROUNDnHead-up tilt testing is widely used in the clinical assessment of patients with unexplained syncope. However, the lack of a standard methodology and the conflicting results concerning sensitivity and specificity of the procedure have prompted further studies to define a more cost-effective approach for tilt testing.nnnOBJECTIVESnOur clinical investigation was undertaken to assess the diagnostic value in unexplained syncope of a simple and time-saving protocol for head-up tilt testing, including low-dose sublingual isosorbide dinitrate administration.nnnPATIENTS AND METHODSnA group of 73 consecutive patients (43 women and 30 men, mean age 39.6+/-21.8 years) with unexplained syncope despite conventional clinical cardiovascular and neurologic assessment and 10 asymptomatic control subjects underwent head-up tilt testing with isosorbide dinitrate challenge. Participants were tilted at 60 degrees for 30 minutes without medication; if no symptoms occurred, 1.25 mg of isosorbide dinitrate was administered sublingually and tilting was continued for an additional 15 minutes.nnnRESULTSnDuring the drug-free phase of the test 14 (19.2%) patients had syncope. After isosorbide dinitrate administration syncope occurred in another 28 patients (38.3%); minor symptoms in association with hypotension developed in 10 (13.7%) patients. The test result was negative in all control subjects. The positive rate and specificity of head-up tilt testing with isosorbide dinitrate provocation were 57.5% and 100%, respectively.nnnCONCLUSIONSnThis new practical diagnostic procedure was found to be fairly sensitive and clearly specific in inducing a vasovagal reflex in patients with syncope of uncertain origin. Consequently, such approach could give a significant contribution in the diagnostic workup of these patients.

Electroencephalographic Correlates of Vasovagal Syncope Induced by Head-Up Tilt Testing

BACKGROUND AND PURPOSEnWe sought to determine whether the introduction of EEG monitoring during head-up tilt testing could significantly improve the understanding of the cerebral events occurring during tilt-induced vasovagal syncope and the potential danger to the patient of this diagnostic procedure.nnnMETHODSnEEG monitoring was performed during head-up tilt testing in a group of 63 consecutive patients (27 males and 36 females; mean age, 41.5 years) with a history of recurrent syncope of unknown origin despite extensive clinical and laboratory assessment.nnnRESULTSnSyncope occurred in 27 of 63 patients (42.8%) during head-up tilt testing and was found to be cardioinhibitory in 11 of 27 (40.7%) and vasodepressor in 16 of 27 (59.3%). All patients with a negative response to head-up tilt testing showed no significant EEG modifications. In patients with vasodepressor syncope, a generalized high-amplitude, 4- to 5-Hz (theta range) slowing of EEG activity appeared at the onset of syncope, followed by an increase of brain-wave amplitude with the reduction of frequency at 1.5 to 3 Hz (delta range). The return to the supine position was associated with brain-wave amplitude reduction and frequency increase to 4 to 5 Hz, followed by restoration of a normal EEG pattern and arousal (mean total duration of syncope, 23.2 seconds.). In patients with cardioinhibitory syncope, a generalized high-amplitude EEG slowing in the theta range was noted at the onset of syncope, followed by a brain-wave amplitude increase and slowing in the delta range. A sudden reduction of brain-wave amplitude then ensued, leading to the disappearance of electrocerebral activity (flat EEG). The return to the supine position did not allow either the immediate resolution of EEG abnormalities or consciousness recovery, both of which occurred after a further time interval (mean total duration of syncope, 41.4 seconds.).nnnCONCLUSIONSnEEG monitoring during head-up tilt testing allowed recording and systematic description of electrocerebral abnormalities developing in the course of tilt-induced vasovagal syncope.

DDD Pacing with Rate Drop Response Function Versus DDI with Rate Hysteresis Pacing for Cardioinhibitory Vasovagal Syncope

Background: The effectiveness of cardiac pacing in preventing vasovagal syncope remains controversial. However, DDI pacing with rate hysteresis has been reported to prevent the recurrence of Cardioinhibitory vasovagal syncope in up to 35% of affected subjects and to reduce the overall incidence of syncopal episodes in the others. Recently, DDD pacing with a new promising rate drop response function (Medtronic Thera‐I model 7960) has become available in clinical practice. Aim of the study: The aim of the present open trial was to test the effectiveness of this new pacing modality in patients with Cardioinhibitory vasovagal syncope. Study population and methods: The study population included 20 patients (12 males and 8 females; mean age 61.1 ± 14 yrs) with recurrent syncope (mean number of prior episode = 6.8, range 5–11) and Cardioinhibitory responses during two head‐up tilt tests: the first diagnostic and the second during drug therapy with either β‐blockade or etilephrine. The study patients were randomized to receive either DDI pacing with rate hysteresis (8 patients) or DDD pacing with rate drop response function (11 patients). The head‐up tilt test performed 1 month after pacemaker implantation was positive in 3 of 12 patients (25%) with DDD pacing with rate drop response function and in 5 of 8 patients (62.5%) with DDI pacing with rate hysteresis. The mean duration of follow‐up was 17.7 ± 7.4 months. During follow‐up no patients with a DDD pacemaker with rate drop response function had syncope, while 3 of 8 patients with a DDI pacemaker with rate hysteresis had recurrence of syncope (P < 0.05). Conclusions: These data suggest that DDD pacing with rate drop response function is effective in Cardioinhibitory vasovagal syncope and may be preferable to DDI pacing with rate hysteresis.

Permanent Cardiac Pacing Versus Medical Treatment for the Prevention of Recurrent Vasovagal Syncope

Background—This clinical investigation was performed to compare the effects of permanent dual-chamber cardiac pacing with pharmacological therapy in patients with recurrent vasovagal syncope. Methods and Results—Patients from 14 centers were randomized to receive either a DDD pacemaker provided with rate-drop response function or the β-blocker atenolol at the dosage of 100 mg once a day. Inclusion criteria were age >35 years, ≥3 syncopal spells in the preceding 2 years, and positive response to tilt table testing with syncope occurring in association with relative bradycardia. The primary outcome was the first recurrence of syncope after randomization. Enrollment was started in December 1997, and the first formal interim analysis was performed on July 30, 2000. By that time, 93 patients (38 men and 55 women; mean age, 58.1±14.3 years) had been enrolled and randomized, although follow-up data were available for all patients (46 patients in the pacemaker arm, 47 patients in the pharmacological arm). The int...

Effects of atorvastatin 80 mg daily early after onset of unstable angina pectoris or non-Q-wave myocardial infarction.

This clinical investigation was designed and undertaken to test the hypothesis that the addition of high-dose atorvastatin (80 mg/day) to conventional medical treatment early after either unstable angina pectoris (UAP) or non–Q-wave acute myocardial infarction (AMI) could reduce ischemic recurrences. x7fx7fx7f All patients consecutively admitted to our institution between January 1999 and July 2001 for UAP or non–Q-wave AMI were prospectively screened for inclusion in the study. In all cases the diagnosis of UAP or non–Q-wave AMI was made in accordance with previously reported criteria. 1 To be enrolled in the trial, patients were required to meet the following criteria: (1) angiographic evidence of severe and diffuse coronary artery disease, that was not amenable to direct revascularization by coronary artery bypass grafting or percutaneous transluminal coronary angioplasty, as determined by a cardiac surgeon and an interventional cardiologist during the index admission; (2) objective evidence of symptomatic reversible myocardial ischemia (0.1 mV ST-segment depression on the electrocardiogram) at a low exercise workload (4 METs) while receiving medical treatment (2 antianginal medications at maximal tolerated doses), as assessed by treadmill ergometry (Bruce’s protocol) before discharge; and (3) left ventricular ejection fraction 35%. Exclusion criteria were the presence of congestive heart failure, the need for continuous use of intravenous antianginal medications, and the presence of any major concurrent illness. The study was planned as an open-label, prospective, randomized, controlled trial with parallel groups. Before enrollment, all patients were receiving maximal conventional combination therapy (nitrates, calcium antagonists, and blockers), including 2 medications at maximal tolerated doses in all cases. All patients provided informed consent to take part in the investigation. At discharge from the hospital, included patients

Gender-Specific Predictors of Functional Outcome after Stroke Rehabilitation: Potential Role of the Autonomic Nervous System

The aim of this study was to assess the impact of cardiac autonomic derangement on gender-associated functional outcome of patients with subacute ischemic stroke undergoing a hospital-based rehabilitation program. The study population included 126 consecutive first-ever stroke survivors (mean age 59.7 ± 11.6 years). Time-domain measures of heart rate variability (HRV) by 24-hour Holter monitoring (HM) were considered in all cases. By the end of the rehabilitation program an unfavorable functional outcome with dependency (Barthel Index score of <75) was found in 27 men (40.3%) and in 31 women (52.5%; p = 0.168). Multivariate analysis demonstrated that high age, low Barthel Index score and low Rankin Scale score on admission were independent predictors of an unfavorable functional outcome in both men and women. The standard deviation of normal-to-normal RR intervals on HM was an independent predictor of rehabilitation outcome only in men (OR 15.29, 95% CI 2.47–46.58, p = 0.001). The presence of insular damage on neuroimaging studies was independently associated with an unfavorable functional outcome only in female (OR 18.89, 95% CI 2.34–71.4, p = 0.006). HRV does not predict functional outcome after rehabilitation in women. Instead, insular damage appears to have a role in determining the final results of rehabilitation in women but not in men.

Variable Cerebral Dysfunction During Tilt Induced Vasovagal Syncope

Electroencephalographic (EEG) monitoring was performed during head‐up tilt testing (HUT) in a group of 63 consecutive patients (27 males, 36 females, mean age 41.5 years) with a history of recurrent syncope of unknown origin despite extensive clinical and laboratory evaluation. Syncope occurred in 27/63 patients (42.8%) during HUT and was cardioinhibitory in 11/27 (40.7%) and vasodepressor in 16/27 (59.3%). All patients with a negative response to HUT had no significant EEG modifications. In patients with vasodepressor syncope a generalized high amplitude 4–5 Hz (theta range) slowing of EEG activity appeared at the onset of syncope, followed by an increase in brain wave amplitude with a reduction of frequency at 1.5–3 Hz (delta range). The return to the supine position was associated with brain wave amplitude reduction and frequency increase to 4–5 Hz, followed by restoration of a normal EEG pattern and arousal (mean total duration of syncope 23.2 s). In patients with cardioinhibitory syncope, a generalized high amplitude EEG slowing in the theta range was noted at the onset of syncope, followed by a brain wave amplitude increase and slowing in the delta range. A sudden reduction of brain wave amplitude ensued leading to the disappearance of electroencephalographic activity (“flat” EEG). The return to the supine position was not followed by immediate resolution of EEG abnormalities or consciousness recovery, both occurring after a longer time interval (mean total duration of syncope 41.4 s). EEG monitoring during HUT allowed the recording and systematic description of electroencephalographic abnormalities developing in the course of tilt induced vasovagal syncope.

Transseptal activation during left atrial pacing in humans: electroanatomic mapping using a noncontact catheter and the intracardiac echocardiography.

AbstractBackground: A better understanding of transseptal activation may be important for the treatment of atrial fibrillation, but little is known about preferential routes of conduction from the left atrium (LA) to the right atrium (RA) in humans.nMethods and Results: Twelve patients were studied. A noncontact mapping system was used to map the RA during pacing from several sites of LA at different cycle lengths. The location of the Bachmanns bundle (BB), the fossa ovalis (FO) and the coronary sinus (CS) ostium were determined using intracardiac echocardiography. The BB was the earliest area of right atrial activation during pacing from the atrial appendage, roof and postero-superior wall in 94% of cases. The FO was the area of earliest activation during pacing from the septum and the right superior pulmonary veins (PV) in 95% of cases. The CS ostium (alone or associated with the FO) was the region of transseptal breakthrough in all patients during pacing from the right inferior PV, postero-inferior wall and distal CS. Various patterns of activation with 2 or 3 distinct areas of transseptal breakthrough were observed during pacing from the lateral wall and the left superior PV. The pacing cycle length did not influence the modality of transseptal activation.nConclusions: Different patterns of transseptal activation were found during pacing from LA. The preferential routes of conduction from the LA to the RA were related to the sites of stimulation and were not influenced by the pacing cycle length.

Ambulatory Blood Pressure Monitoring After Acute Myocardial Infarction

AbstractAim: To assess the usefulness of ambulatory blood pressure monitoring (ABPM) in the prognostic stratification of patients with a recent myocardial infarction.n Method: The study population included 75 patients consecutively admitted at our institution for acute ST-segment elevation myocardial infarction (STEMI). All patients underwent ABPM 3 weeks after discharge and were subsequently followed for 12 months.n Results: The age (Y), mean 24-hour diastolic blood pressure (mDBP) and mean 24-hour beat-to-beat interval (mBBI) values were found to be independent predictors of the combined endpoint of cardiac death and symptomatic left ventricular dysfunction during the follow-up period. A prognostic index was then developed from such variables, according to the formula (mDBP + mBBI/10) − Y. This index, when considered as a categorical variable, in its ‘low’ figures (cut-off <88), showed a significant prognostic value (p < 0.0001). The predictive value of the index for the combined endpoint was higher than left ventricular ejection fraction (50% versus 36%).