Prognostic value of total atrial conduction time measured with tissue Doppler imaging to predict the maintenance of sinus rhythm after external electrical cardioversion of persistent atrial fibrillation.

BACKGROUND: Atrial fibrillation (AF) is the most common sustained arrhythmia, with a high recurrence rate, especially during the first months after cardioversion (CV). Few parameters have been evaluated as predictors for the maintenance of sinus rhythm (SR), with limited results. Recently total atrial conduction time (TACT) has been proposed as independent predictor of AF recurrence. The aim of this study was to investigate the prognostic value of TACT, measured using PA-TDI duration, to predict 1-year maintenance of restored SR after electrical CV. METHODS AND RESULTS: In a population of 104 patients (58 male, aged 70 ± 9) with persistent AF, submitted to external electrical CV, we performed a complete echocardiogram after restoring SR. The TACT was estimated by measuring the time delay between the onset of the P-wave in lead II of the surface electrocardiogram and the peak A'-wave on the tissue Doppler imaging (TDI) tracing of the left atrial lateral wall (so-called PA-TDI duration). After a mean follow-up of 14 ± 2 months, 34 (33%) patients had recurrent AF, whereas 70 (67%) patients maintained SR. At multivariate analysis only PA-TDI was identified as independent predictor of AF recurrence (HR 1.04; 95% CI 1.03-1.06; P < 0.001). Receiver operator characteristics curve analyses demonstrated a high degree of discrimination (area under the curve 0.923); with a cut point of 152 msec, we obtain a good diagnostic accuracy (sensitivity 91%, specificity 87%). CONCLUSION: The TACT using TDI is an independent predictor of AF recurrence and can be used to predict the maintenance of SR after external electrical CV.

Role of echocardiographic dyssynchrony parameters in predicting response to cardiac resynchronization therapy.

AIMS: In the present study, we compare different echocardiographic cardiac dyssynchrony parameters, both of intraventricular and interventricular dyssynchrony, in order to predict response to cardiac resynchronization therapy (CRT). METHODS AND RESULTS: In a population of 77 heart failure patients scheduled for CRT, we measured the interventricular mechanical delay (IVMD) and we analyzed six different parameters of intraventricular dyssynchony: the tissue Doppler imaging (TDI) septum-lateral wall delay, the systolic dyssynchrony index; the three-dimensional SD of the time to reach minimum systolic volume for 16 left ventricular segments (3D-SDI); the speckle-tracking radial, circumferential and longitudinal dyssynchrony. At 6 months of follow-up, 61 (79%) patients were responders (≤15% in left ventricular end-systolic volume). On baseline analysis, 3D-SDI, radial strain, longitudinal strain and circumferential strain and IVMD were significantly higher in responder group (10.8 ±â€Š3.9 vs. 7.6 ±â€Š1.8% for 3D-SDI; P = 0.003; 212 ±â€Š91 vs. 125 ±â€Š36 ms for radial strain, P = 0.0003; 185 ±â€Š83 vs. 134 ±â€Š53 ms for longitudinal strain, P = 0.02; 190 ±â€Š80 vs. 130 ±â€Š54 ms for circumferential strain, P = 0.006; 45 ±â€Š21 vs. 30 ±â€Š20 ms for IVMD; P = 0.01). On univariate and multivariate analysis, only IVMD was significantly associated with a complete echocardiographic response to CRT. 3D-SDI and radial strain present the better values of sensitivity and specificity, overall if associated to an evaluation of IVMD (sensitivity 76%, specificity 88%, for 3D-SDI + IVMD; sensitivity 80% and specificity 85% for radial strain + IVMD). CONCLUSION: The novel parameters, such as 3D-SDI and speckle-tracking (particularly radial strain), offer better diagnostic accuracy in identifying patients who are responders to CRT. The addition of the contemporary parameter of IVMD improves the diagnostic accuracy.

[Herbs and cardiotoxic effects]. / Cardiotossicità da erbe selvatiche.

Accidental or deliberate ingestion of poisonous herbs has become an increasingly common phenomenon over the last years. From existing literature data and case reports from emergency room visits or poison control centers, an overview is presented of the potential cardiotoxic manifestations following intoxication by wild herbal plants of the territory. The effects of the consumption of cardiac glycoside-containing plants (e.g., digitalis) are discussed along with tachyarrhythmias induced by Aconitum napellus L., Atropa belladonna L., Mandragora officinarum L. or Ephedra distachya L. herbs, and hypertensive crises associated with licorice abuse. For each plant, a brief historical and botanical background is provided, focusing on pathophysiology of intoxication and cardiotoxic effects on the basis of the most recent literature. Finally, medical management of intoxication, from both a general and cardiological viewpoint, is reviewed.

Usefulness of three-dimensional transthoracic echocardiography in particular clinical settings: a case of aorto-cavitary fistula in periprosthetic aortic valve abscess.

Prosthetic valve endocarditis (PVE) due to staphylococcus aureus is associated with high morbidity and mortality. Paravalvular abscess formation is a common complication of PVE at the aortic position, but fistula formation is rarely seen. The transesophageal echocardiography is the "gold-standard" exam to detect PVE. We present a case of a 69-year-old patient with prosthetic aortic valve endocarditis, paravalvular abscess, and fistula in right atrium, where the diagnosis was made with three-dimensional transthoracic echocardiography, without transesophageal evaluation.

Transthoracic second harmonic two- and three-dimensional echocardiography for detection of patent foramen ovale.

AIMS: Transoesophageal echocardiography (TEE) with contrast administration is still considered as the reference method for the detection of patent foramen ovale (PFO) with interatrial shunt, but it is a semi-invasive exam. The aim of the present study is to evaluate a role of two- and three-dimensional transthoracic echocardiography (TTE and R3DTE) as a diagnostic alternative to transcranial Doppler ultrasound (TCD) and TEE for detection of atrial right-to-left shunt. METHODS AND RESULTS: Seventy-five patients with history of cerebrovascular events were subjected to four diagnostic examinations: TCD, TTE, R3DTE, and TEE, with bubble contrast. Bubbles in the left atrium within three cardiac cycles were considered diagnostic for PFO and later as a pulmonary shunt. Greater than 20 bubbles in the left atrium were considered a large shunt and <20 a small shunt. Every exam was read blinded to the results of the others. From the 75 enrolled patients, 62 (82.6%) patients showed right-to-left shunt with TEE; the results were also positive in 53 patients using TCD (70.6%), in 53 using R3DTE (70.6%), and in 55 using TTE (73.3%) (P = NS). There is a statistically significant superiority for TEE in the capacity of detecting shunts compared with TCD (P < 0.024), TTE (P < 0.018), and R3DTE (P < 0.018). The TEE presents a superior ability to recognize mild/moderate interatrial shunts respect to other exams (P = 0.003), without differences for shunts of high degree. In comparison to the TEE, the sensitivity is 89% for TTE, 88% for R3DTE, and 85% for TCD; the specificity is 100% for TTE and R3DTE, and 90% for TCD; the positive predictive value is 100% for TTE and R3DTE, and 98% for TCD; and the negative predictive value is 65% for TTE, 65% for R3DTE, and 53% for TCD. Considering only for mild/moderate shunts, the diagnostic accuracy is clearly inferior (sensitivity 63% for TTE, 58% for R3DTE, and 53% for TCD). CONCLUSION: In this cohort of patients, TEE confirms the role of 'gold standard' exam for the detection of PFO; the non-invasive methods, and the TTE in particular, present a good diagnostic accuracy, but are inferior to the TEE because of the low negative predictive value and the non-optimal detection of small shunts. If the only purpose of TEE is the detection of significative interatrial shunt, TEE can be replaced by TTE. The R3DTE presents a good diagnostic accuracy, provides a better anatomical definition of the interatrial septum, and may have a role in this setting of patients, but does not add a lot to the TTE for the diagnosis.

Atypical arrhythmic complications in familial hypokalemic periodic paralysis.

Familial hypokalemic periodic paralysis is an autosomal dominant muscle disorder characterized by episodic attacks of muscle weakness, accompanied by a decrease in blood potassium levels. It is based on genetic mutations in the genes CACNA1S (most frequent, encoding the skeletal muscle calcium channel) and SCN4A (10% of cases, encoding the sodium channel). Few cases have been reported with cardiac dysrhythmia. We report a rare case of a patient with a novel SCN4A mutation who presented, on ECG, extreme bradycardia and syncopal sinus arrest that required a temporary pacemaker implant

Digitalis must be banished from the table: a rare case of acute accidental Digitalis intoxication of a whole family.

Advanced Digitalis intoxication is a rare event, mainly associated with overdose in patients with Digitalis therapy. We report an unusual case of acute 'familiar' digitalis poisoning in three patients who had eaten potato dumplings flavoured with leaves of Borago officinalis L. unconsciously mixed with leaves of Digitalis purpurea L. A complicated clinical course with marked bradyarrhythmias was presented, with good evolution thanks to the use of digoxin-specific antibody Fab fragments. The theme of the domestic use of plants with medicinal effects has been treated and discussed.

Biventricular pacemaker lead thrombosis: a rare case treated with surgical thrombectomy.

Right cardiac thrombosis is an infrequent complication after pacemaker implant. We report a patient who received a biventricular implantable cardioverter defibrillator, with a large mobile thrombus, adherent to the left ventricular lead. This catheter was partially dislocated, with a large, mobile loop through the right atrium and right ventricle; so the lead thrombus could alternately obstruct the pulmonary valve and the tricuspid valve. We believe that this is the first case of left ventricular lead thrombosis, in which the surgical treatment included thrombectomy with conservation of the catheter that was anchored to the internal right atrial wall in order to limit its great motility, maintaining the contribution to the cardiac resynchronization.

[Effects of pretreatment with amiodarone infusion in patients with persistent atrial fibrillation submitted to external electrical cardioversion: a single center experience]. / Effetti del pretrattamento con infusione di amiodarone in pazienti affetti da fibrillazione atriale persistente, sottoposti a cardioversione elettrica esterna: esperienza di un singolo centro.

BACKGROUND: Several studies demonstrated the efficacy of amiodarone pretreatment in achieving bet-ter outcomes after electrical cardioversion of atrial fibrillation. In the majority of cases, oral amiodarone for at least 1 month was administered, with the result of lengthening of pre-cardioversion time. Only one study in the literature reported high-dose amiodarone infusion, showing an increase in the incidence of slow arrhythmias. The aim of this study was to test the efficacy of pretreatment infusion of a single dose of amiodarone few hours before electrical cardioversion in restoring sinus rhythm and reducing the incidence of early arrhythmic recurrences. METHODS: The study was retrospective. We analyzed a population of 155 patients with persistent atrial fibrillation, from May 2003 to November 2005. The first group of 86 patients was treated with amiodarone at the dose of 4 mg/kg in 30 min, few hours before electrical cardioversion; the second group of 69 patients was treated with electrical cardioversion without pharmacological pretreatment. The two groups were homogeneous for age, sex, coronary artery disease, duration of arrhythmia, atrial dimensions, left ventricular ejection fraction, and paddle position for electrical cardioversion. RESULTS: There were no significant differences between the two groups in terms of efficacy of cardioversion (95.3 vs 91.3%, p = NS). Pretreatment with bolus of amiodarone significantly reduced the incidence of immediate recurrence (3.5 vs 17.4%, p < 0.05) and the mix of immediate and early recurrence (19.7 vs 33.3%, p < 0.05). There were no significant differences in the incidence of late recurrences (17.4 vs 13%, p = NS). There were no significant bradyarrhythmias in the two groups. Amiodarone pretreatment did not reduce energy delivery to obtain cardioversion. CONCLUSIONS: Amiodarone pretreatment with intravenous bolus few hours before electrical cardioversion reduces short-term recurrences of atrial fibrillation. It does not reduce energy delivery of electrical cardioversion and does not increase the incidence of slow arrhythmias. Randomized prospective studies are warranted to confirm these findings.

Interventricular cardiac resynchronization with right ventricular apical pacing in a patient with Ebstein's defect.

We present the case of a patient with Ebstein's defect surgically corrected, and a complete right bundle branch block (RBBB) documented on echocardiogram. After an episode of near syncope due to a high-grade atrioventricular (AV) block, the patient was assisted with a bicameral DDDR pacemaker implanted with traditional right ventricular apical pacing. After the DDDR, and after stimulation with an AV delay of 180 ms, a narrow QRS complex was observed. Meanwhile, the typical left bundle branch block morphology of the right ventricular pacing and the native RBBB morphology were missing. The QRS complex narrowing persisted, even with physical activity and also with the heart rate progression. An echocardiographic study confirmed an improvement of the cardiac resynchronization parameters with this programmed stimulation.

Left ventricular pseudoaneurysm: an atypical case associated with a small ventricular septal defect.

We present an atypical case of postinfarction left ventricular pseudoaneurysm involving the posterobasal septal wall, with protrusion into the right ventricle, associated with a small septal defect and left-to-right shunt. In this case, a conservative approach was adopted rather than surgical management, and the patient had a good clinical outcome. Subsequent evaluation with two-dimensional colour Doppler, three-dimensional echocardiography and 16-slice computed tomography is reported.