urlanello F

Clinical efficacy of ivabradine in patients with inappropriate sinus tachycardia: a prospective, randomized, placebo-controlled, double-blind, crossover evaluation.

OBJECTIVES The purpose of this study was to investigate the role of ivabradine in the treatment of symptomatic inappropriate sinus tachycardia using a double-blind, placebo-controlled, crossover design. BACKGROUND Due to its I(f) blocking properties, ivabradine can selectively attenuate the high discharge rate from sinus node cells, causing inappropriate sinus tachycardia. METHODS Twenty-one patients were randomized to receive placebo (n=10) or ivabradine 5 mg twice daily (n=11) for 6 weeks. After a washout period, patients crossed over for an additional 6 weeks. Each patient underwent symptom evaluation and heart rate assessment at the start and finish of each phase. RESULTS After taking ivabradine, patients reported elimination of >70% of symptoms (relative risk: 0.25; 95% CI: 0.18 to 0.34; p<0.001), with 47% of them experiencing complete elimination. These effects were associated with a significant reduction of heart rate at rest (from 88±11 beats/min to 76±11 beats/min, p=0.011), on standing (from 108±12 beats/min to 92±11 beats/min, p<0.0001), during 24 h (from 88±5 beats/min to 77±9 beats/min, p=0.001), and during effort (from 176±17 beats/min to 158±16 beats/min, p=0.001). Ivabradine administration was also associated with a significant increase in exercise performance. No cardiovascular side effects were observed in any patients while taking ivabradine. CONCLUSIONS In this cohort, ivabradine significantly improved symptoms associated with inappropriate sinus tachycardia and completely eliminated them in approximately half of the patients. These findings suggest that ivabradine may be an important agent for improving symptoms in patients with inappropriate sinus tachycardia.

Transesophageal atrial pacing: A first-choice technique in atrial flutter therapy

Here we report on a study of 181 episodes of spontaneous atrial flutter (AF) (mean atrial cycle length 250 +/- 32 msec) treated by transesophageal atrial pacing (TAP) in 138 patients (92 men and 46 women; mean age 59.5 +/- 12.6 years). TAP was effective in 163 episodes (90%); sinus rhythm resumption was immediate in 36 (19.9%) and followed a short period of atrial fibrillation in 64 (35.3%); in 63 episodes (34.8%) a stable atrial fibrillation was obtained. TAP was unsuccessful in 18 cases (10%). All the patients tolerated the procedure well. A statistical elaboration with the Fisher exact test did not evidence a correlation between efficacy and age, sex, atrial cycle length, or underlying heart disease but showed a significant correlation between efficacy and AF duration of less than 1 day (p less than 0.05) and absence of antiarrhythmic pharmacologic pretreatment (p less than 0.01). These data strongly support the immediate first-choice use of TAP in AF therapy.

Catheter ablation of Wolff-Parkinson-White syndrome associated with congenital absence of inferior vena cava.

In the present report we describe a patient (a 36-year-old woman with 15 year history of supraventricular tachyarrhythmias) with congenital absence of inferior vena cava (IVC) revealed during radiofrequency (RF) catheter ablation procedure for right postero-septal Wolff-Parkinson-White syndrome (WPW). For the absence of IVC, the ablation procedure was more difficult, because we had to perform the ablation with the catheters (the ablator catheter and the coronary sinus catheter) introduced both through the superior vena cava. The application of RF energy (35 Watt for 60 seconds) at successful site abolished accessory pathway conduction. The following day was performed the venous angiography, showing the absence of the IVC and a venous return via paravertebral venous plexus to the azygous vein and superior vena cava into the right atrium. Computer tomography confirmed the absence of the IVC with azygous continuation. The drainage via the azygous system modified the radiological image on chest roentgenogram of the right mediastinal silhouette. During cardiogenesis fusion of the IVC and organisation of the heart occur between the 33rd to 40th embryonic days. It is therefore possible that some unknown teratogenic mechanism at this critical period might have caused, in the patient, both the developmental arrest of IVC and failure of regression of atrio-ventricular anatomical and electrical continuity in the right postero-septal region.

Left atrial rhythm. Vectorcardiographic study and electrophysiologic critical evaluation

Abstract The electrocardiographic diagnosis of left atrial rhythm is usually based on the polarity of the P wave, i.e., on the orientation of the principal vectors of the P wave. The validity of this interpretation rests on the assumption of a uniform spread of activation from the pacemaker to the atrial muscular mass. Experimental investigations in animals and humans have shown the existence of a specific atrial conductive tissue not yet completely elucidated from anatomical and functional points of view. Conflicting results have been observed between the reproduction of ectopic left atrial rhythms and the electrocardiographic implication based on the polarity of the P wave. Since the morphologic assessment of the atriogram give a more faithful representation of the vectorial direction and sequence of the ectopic rhythm, vectorcardiographic analysis was made of seven patients who had an electrocardiographic diagnosis of left atrial rhythm. ∗ ∗The study of the morphology and the duration of P loop and of the direction and voltage of the greatest vector strongly suggests an ectopic origin of the pacemaker but does not definitely indicate its location in the left atrium.For these reasons, we propose the general term of ectopic rhythm instead of left atrial rhythm.

'Orphan drugs' in cardiology: nadolol and quinidine.

The recent withdrawal from the market of nadolol (Corgard; Bristol-Myers Squibb, Sermoneta, Italy) and quinidine polygalacturonate (Ritmocor; Malesci, Bagno A Ripoli, Italy) has been causing clinical problems to many cardiologists and patients, frequently leading to discontinuance of an effective and well-tolerated pharmacological treatment. Nadolol is useful in the treatment of severe and refractory arrhythmias, particularly in some genetically determined ion-channel diseases, such as long-QT syndrome and catecholaminergic polymorphic ventricular tachycardia.Quinidine is still used in refractory atrial fibrillation recurrences. Recent studies have demonstrated the clinical efficacy of quinidine in the treatment of rare genetically determined ion-channel diseases at high risk of sudden death, such as Brugada syndrome and short-QT syndrome.We hope that scientific societies can influence healthcare and pharmaceutical institutions, in order to restore the availability of two cardiovascular drugs that are extremely important in the care of arrhythmic patients.

Clinical and electrocardiographic features of complete heart block after blunt cardiac injury: A systematic review of the literature

The underlying mechanisms and temporal course of complete heart block (CHB) after blunt cardiac injuries (BCIs) are poorly understood, and a systematic analysis of available data is lacking. In this systematic review, PubMed was searched for publications of reported cases of CHB-BCI analyzing clinical findings, electrocardiographic features, temporal course, and outcomes. Case reports on CHB-BCI were available for 50 patients, mainly secondary to traffic or sport accidents. A fatal outcome occurred in 10 of 50 (20%) of patients, while a structural damage of the atrioventricular (AV) conductive system was evident in 4 of 8 (50%) of necropsy studies. Clinical manifestation of CHB-BCI occurred within 72 hours of injury in 38 of 47 (∼80%) of patients, and 1:1 AV conduction was restored within 7-10 days in about half of early survivors. Permanent pacemaker implantation was indicated in 22 of 42 (∼50%) of early survivors because of recurrent or permanent CHB. Cardiac troponins, when analyzed, were elevated in 12 of 13 (∼90%) of patients, and electrocardiographic features of aberrancy were present in 29 of 40 (>70%) of patients. In conclusion, CHB secondary to BCI is associated with 20% mortality mainly occurring in the early posttraumatic period and most of the deaths are due to or triggered by this malignant arrhythmia. Recurrent or permanent CHB requiring pacemaker implantation occurs in ∼50% of survivors. A structural damage of the AV conductive system can be found in 50% of necropsy studies.

Long-term follow-up of patients with inducible supraventricular tachycardia treated with flecainide or propafenone: Therapy guided by transesophageal electropharmacologic testing

We report our experience with flecainide and propafenone therapy for inducible supraventricular tachycardias and paroxysmal supraventricular tachycardias due to atrioventricular (AV) nodal reentry or the Wolff-Parkinson-White syndrome. We performed an electropharmacologic test (ET) that consisted of first inducing a clinical arrhythmia by transesophageal atrial pacing (TAP) protocol. This was followed by intravenous drug administration and TAP reevaluation, either after acute intravenous administration or in oral steady-state. We used ET with flecainide and/or propafenone to study 2 groups of patients at least 3 years before the long-term clinical observation period. The first group was comprised of 58 patients with reciprocating tachycardias--due to AV node reentry in 17 (29.3%) and anomalous pathway in 41 (70.7%). Twelve (29.3%) of the latter had reciprocating tachycardias, 15 (36.6%) had atrial fibrillation, and 14 (34.2%) had both arrhythmias. During ET, flecainide was administered to 42 patients, and the ET was considered positive in 28 (66.7%). Propafenone was administered to 32 patients, with positive results in 15 (46.9%). In 15 patients, both flecainide and propafenone were tested, 8 receiving flecainide after a negative ET with propafenone, and 7 receiving propafenone after a negative ET with flecainide. In the first group, the ET was positive in 7 (87.5%), and in the second group, it was positive in 3 (42.9%). In a follow-up of 40.1 +/- 11 months, 38 (65.5%) patients had positive outcomes, 5 (8.6%) had to stop receiving the drugs because of side effects, 3 (5.2%) stopped because of inefficacy, and 12 (20.7%) dropped out.(ABSTRACT TRUNCATED AT 250 WORDS)

Commotio Cordis and complete heart block: Where is the block level?☆

Ventricular fibrillation is typically the initial arrhythmia in commotio cordis following precordium impacts that occur within an electrically vulnerable period of the cardiac cycle. Conversely, complete heart block is very rare in this context, and its mechanism and temporal course are poorly understood. The presented case concerns a 12-year-old boy, athletic skier, who developed a transient complete heart block following commotio cordis. The electrocardiographic features, the proposed block level and mechanisms of complete heart block following commotio cordis are discussed.

Cancer, Heart Diseases and Common Risk Factors: Diet and Physical Activity

Lifestyle and diet are recognized as risk factors determinants in the pathogenesis of cancer and cardiovascular disease. Cardiovascular diseases and many cancers share the same risk factors, and the strategies useful to prevent cardiovascular diseases are often useful to prevent various kinds of cancer and vice versa. Reduction in sugar-sweetened beverages is important for reducing both cardiovascular and cancer risk in individuals. Whole grain foods substantially lower the risk of CAD, diabetes, and cancer and also play a role in body weight management and digestive health; high consumption of whole grains or cereal fiber was significantly associated with reduced risk of all-cause mortality and death from CVD, cancer, diabetes, respiratory disease, infections, and other causes. There is a strong concordant evidence that fruit (both fresh and nuts) and vegetable consumption lowers CVD and cancer risk. There are significant differences amongst the different types of fruits, vegetables, or their juices, according to the way they are cultivated (open air versus green houses; southern versus northern countries). To obtain the most beneficial effects, the diet should include a large variety of different fruits and vegetables, preferring season foods. The cardiovascular and cancer risk linked to eating meat is mostly due to the quality (fresh or processed) and the type of cooking. A moderate intake of meat seems to be safe. Dairy foods are a good source of proteins, calcium, and other nutrients and should not be banned from the diet. However, they should be used as an alternative to meat in the meal. Lowering the sodium intake is beneficial for preventing both cardiovascular diseases and stomach cancer. A diet including a variety of foods (different fruits and vegetables) is likely to provide the necessary amount of vitamins and micronutrients. The intake of dietary supplements (or of “fortified foods”) is not recommended.

Cardiac Arrhythmias in Drug Abuse and Intoxication

Cardiac arrhythmias are common in acute intoxication, although epidemiological data are often restricted to specific substances. A 10 % incidence of cardiac arrhythmias during acute intoxication has been reported by a referral poison center in Germany that analyzed the data of 91,285 patients referred between 1995 and 2003 using the inquiries of physicians and paramedics [1].