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Purpose: During incremental atrial pacing in patients with atrioventricular nodal reentrant tachycardia, the PR interval often exceeds the RR interval (PR > RR) during stable 1:1 AV conduction. However, the PR/RR ratio has never been evaluated in a large group of patients with pacing from the proximal coronary sinus and after isoproterenol challenge. Our study validates new site of pacing and easier method of identification of PR > RR., Material and Methods: A prospective protocol of incremental atrial pacing from the proximal coronary sinus was carried out in 398 patients (AVNRT-228 and control-170). The maximum stimulus to the Q wave interval (S-Q = PR), SS interval (S-S), and Q-Q (RR) interval were measured at baseline and 10 min after successful slow pathway ablation and after isoproterenol challenge (obligatory)., Results: The mean maximum PR/RR ratios at baseline were 1.17 ± 0.24 and 0.82 ± 0.13 (p < 0.00001) in the AVNRT and controls respectively. There were no PR/RR ratios ≥1 at baseline and after isoproterenol challenge in 12.3% of the AVNRT group and in 95.9% of the control group (p < 0.0001). PR/RR ratios ≥1 were absent in 98% of AVNRT cases after slow pathway ablation/modification in children and 99% of such cases in adults (P = NS). The diagnostic performance of PR/RR ratio evaluation before and after isoproterenol challenge had the highest diagnostic performance for AVNRT with PR/RR > = 1 (sensitivity: 88%, specificity: 96%, PPV-97%, NPV-85%)., Conclusions: The PR/RR ratio is a simple tool for slow pathway substrate and AVNRT evaluation. Eliminating PR/RR ratios ≥1 may serve as a surrogate endpoint for slow pathway ablation in children and adults with AVNRT., (Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.)

Objectives: The purpose of this study was to prospectively evaluate the feasibility and diagnostic value of right ventricular overdrive pacing (RVOP) during supraventricular tachycardia (SVT) using a 2-catheter approach with automatic pacing from the right ventricular inflow (RVIT) and outflow tract (RVOT)., Methods: One hundred and thirty-six consecutive patients (with 138 arrhythmias, mean age 36 ± 20 years, range 4-95) were enrolled in this study. Only coronary sinus and ablation catheters were used. RVOP was delivered from RVIT and then from RVOT. Each attempt consisted of 10 synchronized beats delivered at a cycle length of 10-40 ms longer than the tachycardia cycle length., Results: RVOP was sufficient to confirm the transition zone within the first 9 beats in the majority of SVTs. Atrial perturbation (acceleration, delayed) in the transition zone was detected in all patients with orthodromic atrioventricular (AV) reentry. Patients with typical AV nodal reentry, atypical AV nodal reentry and atrial tachycardia did not show atrial timing perturbation during fusion complexes of RVOP., Conclusions: Synchronized RVOP from RVIT or RVOT is an easy and accurate method for the quick and reliable differential diagnosis of SVT in various clinical settings, particularly when only a limited number of catheters are used.

Lead-dependent infective endocarditis (LDIE) has emerged as a serious complication of electrotherapy in the era of advanced medical technology and is a growing problem due to greater patient longevity, limited electrode life-time, an increasing number of abandoned leads, and subclinical symptoms. We present a case of dramatic course of LDIE in a 26 year-old patient in whom standard management had failed to cure endocarditis. This case was complicated by extensive pulmonary septic emboli and required cardio-thoracic intervention.

We present a case of 75-year-old man with numerous inappropriate interventions of an implanted cardioverter-defibrillator (ICD). In this patient with ischaemic cardiomyopathy, ICD was implanted for primary prevention of sudden cardiac death following recurrent syncope. ICD interrogation and non-invasive electrophysiologic study (NIPS) confirmed a risk of reentry-mediated tachycardia and excluded the presence of a manifest or concealed accessory pathway. Invasive electrophysiologic study revealed a wide zone that triggered atrioventricular nodal reentrant tachycardia, and ablation of the slow pathway resulted in complete remission of the arrhythmia. NIPS performed using atrial and ventricular ICD leads and subsequent ICD interrogation confirmed long-term effectiveness of the procedure. At the same time, clinical improvement of heart failure was seen, leading to a suspicion of tachycardia-induced cardiomyopathy coexisting with ischaemic cardiomyopathy.

Clay aerogels, ultra low density materials made via a simple freeze-drying technique, have shown much promise in broad applications because of their low densities, often in the same range as silica aerogels (0.03-0.3 g/cm(3),) but suffering from low mechanical strength. A bioinspired approach to mineralize an active polymer/clay aerogel composite is inspected, showing marked improvement of the mechanical properties with increasing modification. Further property improvement was achieved using a layer-by-layer approach to produce alternate layers of polymer and silica on the surface.

Electrocardiogram is commonly used in the diagnosis of cor pulmonale in patients with chronic obstructive pulmonary disease (COPD). Pulmonary hemodynamics being the definite method for diagnosis the disease can be used to vary the ecg criteria for diagnosis cor pulmonale. After excluding patients with old myocardial infarction and with pulmonary wedge pressure > 12 mm Hg in 66 patients aged 65.2 with advanced COPD (FEV1 0.78 +/- 0.3 litre) pulmonary hemodynamics and ecg were performed at the same time. The signs of right ventricular hypertrophy were sought for using 3 sets of criteria: the World Health Organisation criteria, new compiled Lehtonen et al. Criteria and right ventricular precordial leads. WHO criteria had a specificity and sensitivity of 50% and 57.6%, the modified right precordial leads-53% and 64.5% and compiled Lehtonen's criteria -57% and 59% respectively. In 32 patients with mild pulmonary hypertension (20-29 mm Hg) sensitivity of WHO criteria was 46.8%, right precordial leads -51.6%, and Lethonen and co. Criteria -50%, in 10 patients with moderate pulmonary hypertension (30-39 mm Hg) 59%-62.5%-50%, in 9 patients with severe hypertension (> or = 40 mm Hg) 100%-100%-100% respectively. Our studies confirm the poor sensitivity and of ecg criteria for diagnosis of cor pulmonale (pulmonary hypertension) in COPD. However, in mild and moderate pulmonary hypertension, sensitivity of ecg diagnosis of cor pulmonale is improved if right modifieds precordial leads are used. New, compiled Lehtonen's criteria failed to improved diagnosis of diagnosis of cor pulmonale. All studied sets of criteria are highly sensitive in COPD patients with severe pulmonary hypertension.

Both oral and intravenous ipratropium bromide were assessed clinically, electrocardiographically and electrophysiologically in 15 patients with symptomatic bradycardia, aged between 32 and 79 years. Ipratropium bromide administered intravenously accelerated heart rate by more than 30% in the majority of patients. Electrophysiologically it normalized conduction time and sinus node response. Electrophysiological studies did not enable to foreseen the efficiency of oral form which may be useful in the treatment of symptomatic bradycardia in increased parasympathetic tone and both mild, and moderate sinus node insufficiency.

A 51-year-old patient with COPD, obesity, and pulmonary hypertension underwent long-term prazosin therapy after a successful hemodynamic response to 1 mg of oral prazosin. The 18-month administration of prazosin, in a dose of 3 mg a day, resulted in continued hemodynamic and echocardiographic benefits.

Chronic enalapril therapy was assessed in 11 patients with cor pulmonale due to chronic obstructive pulmonary disease. Enalapril was added to the maintenance dose of diuretics and digitalis and when clinical stabilisation was achieved haemodynamics, spirometry, blood gases and maximal treadmill exercise test accompanied by +pulse oximetry were performed before and after 30 days, 10-20 mg a day, enalapril therapy. Haemodynamic study showed moderate but significant decrease in mean pulmonary artery pressure, from 24 +/- 3 to 21 +/- 5 mmHg (p = 0.05). There were no substantial differences in cardiac output as well as in blood gases and spirometry after enalapril therapy. Slight decrease in oxygen delivery, on an average from 9157 +/- 3808 to 8074 +/- 3574 (p = NS), was accompanied by a concomitant fall in haemoglobin. We noted significant improvement of maximal exercise test results after enalapril therapy. Maximal workload achieved and the time of exercise increased. It was accompanied by subjective improvement as assessed by Borg scale. We observed no adverse effects of enalapril during one month therapy in patients with cor pulmonale and COPD.

The value of vasodilatatory treatment of pulmonary hypertension due to chronic obturative pulmonary disease (c.o.p.d.) is still controversial. However in patients with c.o.p.d. causal treatment as well as chronic domestic oxygen therapy have a wide range of limitations. Among vasodilator alpha-1 blockers show less vasodilator-related adverse effects, and as known from acute trials they exert a potent effect on pulmonary circulation in patients with pulmonary hypertension and c.o.p.d. Prazosin was studied in 11 patients (10 men, 1 women) aged 63 +/- 7 years with advanced c.o.p.d. (FVC 1.8 +/- 0.41, FEV1 0.99 +/- 0.55 l) (s) after their clinical stabilisation. In 4 of them prazosin was added to the maintenance dose of diuretics and digitalis. Subjective status, NYHA functional class, spirometric (FVC, FEV1) and gaseous (PaO2, PCO2) parameters, weight, systemic blood pressure, and heart rate were noted. During Swan-Ganz catheterization mean pulmonary artery pressure (MPAP), right ventricular end-diastolic pressure (RVEDP), pulmonary wedge pressure (PCWP), cardiac output (CO), systemic (SVR) and pulmonary (PVR) vascular resistance were measured. The acute trial with 1 mg prazosin taken orally was followed by 2- and 6-week of 3 mg prazosin treatment assessment. After a single dose of 1 mg prazosin there was a significant decrease in MPAP from 36 +/- 9 to 28 +/- 10 (p = 0.001) and 44% decrease in RVEDP (p = 0.05). CO increased by 16% (p = 0.01). The fall in PVR (30%, p = 0.01) exceeded that in SVR (17%, NS). No adverse effects were observed. During 2-week 3 mg a day prazosin therapy 2 patients were excluded following dyspnea and systemic hypotonia.(ABSTRACT TRUNCATED AT 250 WORDS)

Authors presented intravitally diagnosed and well echocardiographically supplied documentary evidence for a huge thrombus positioned in the left atrioventricular ostium in a 52 years old woman within two months of Björk-Shiley mitral valve replacement because of a mitral valve disease.