Ventricular Extrasystolic Beats Research Articles

Efficacy of Catheter Ablation Using the Electroanatomical System without the Use of Fluoroscopy in Patients with Ventricular Extrasystolic Beats.

Catheter ablation (CA) has become safe and efficient for the treatment of patients with ventricular extrasystolic beats (VEBs). The three-dimensional electroanatomic mapping (EAM) system allows the elimination of fluoroscopy time during CA procedures. Non-fluoroscopy CA is a challenging procedure requiring intimate knowledge of cardiac anatomy in patients with VEBs. The study aimed to evaluate the efficacy and safety of the non-fluoroscopy CA using the EAM system in patients with VEBs. Completely fluoroless CA of VEBs guided by EAM was performed in 86% (94 out of 109) of consecutive patients with VEBs. The remaining 15 patients underwent conventional fluoroscopy-guided CA. Demographic and clinical baseline characteristics, procedure parameters, and following complications were obtained from the medical records. Primary outcomes were the acute procedural success rate, the permanent success rate (6-month follow-up), complications, and procedure time. There were no significant differences between groups regarding baseline characteristics. Acute procedural success was achieved in 85 patients (90%) in the non-fluoroscopy group and in 14 patients (93%) in the fluoroscopy group (ns). A long-term success rate was achieved in 82 patients (87%) in the non-fluoroscopy group and in 14 (82%) patients in the fluoroscopy group (ns). The median procedure time was 85 min in the non-fluoroscopy group and 120 min in the fluoroscopy group (p = 0.029). There was only one major complication in the non-fluoroscopy group (ns). Completely fluoroless CA of VEBs guided by EAM is a feasible, safe, and efficient procedure.

Wpływ przezcewnikowego zamknięcia przetrwałego otworu owalnego u pacjentów z udarem kryptogennym na zaburzenia rytmu serca- obserwacja 3-miesięczna

Background: Patent foramen ovale (PFO) is a common abnormality, occurring in about 25% of the population. Percutaneous PFO closure is recommended for selected patients in the prevention of recurrent thromboembolic events. Although transcatheter closure of PFO is recognized as a safe procedure, potential complications, such as atrial fibrillation, may occur. The purpose of this study was to assess the prevalence of arrhythmia in patients before and after PFO closure. Methods: We retrospectively reviewed the medical records of 45 patients (median age, 45 [IQR, 35–61] years; 80% female) who underwent percutaneous PFO closure. 24‑hour Holter electrocardiograms were done both before and 3 months after the procedure in 21 patients (median age, 49 [38–65] years; 81% female), however data of predominant underlying rhythm was available for all 45 patients. Results: There were no statistically significant differences in maximal and minimal heart rate, number of supraventricular and ventricular extrasystolic beats, pauses, episodes of supraventricular and ventricular tachycardia in patients before and after the PFO closure procedure. Median average heart rate was significantly higher before the procedure (70 [67–78] bpm vs 69 [62–77] bpm; p = 0,03). Among the 45 patients, one had a history of paroxysmal atrial fibrillation (AF) before the procedure. During the follow‑up, no AF was found. Conclusions: 1) Transcatheter closure of PFO did not affect arrhythmias observed in 24‑hour Holter ECG monitoring of our patients. 2) The procedure has a low risk of complications if performed in selected patients by an adequately trained operator in an experienced center.

P257 Multiple clinical manifestations of catecholamine secreting paraganglioma

Abstract A 37 years old woman was referred to our hospital due to the onset since the previous day of vertigo associated with nausea and headache. Her previous history revealed an hospitalization ten years before for Tako Tsubo Cardiomyopathy, during which the diagnosis of left temporo-jugular catecholamine secreting paraganglioma was made. Subsequently, there were several hospitalizations for multiple cardiac manifestations, such as acute coronary syndrome during hypertensive crisis, acute pulmonary oedema, one relapse for TakoTsubo syndrome and then an episode of torsade de pointes (TdP) during hypokalemia and elongated QT. The surgical removal of the mass was always rejected by the patient, and therefore, only radiotherapy was performed with significant reduction of the tumour dimensions. Moreover, alpha and beta adrenergic blockers were always administrated. At the admission, she complained neurological symptoms, in particular balance disorder and dysmetria. Brain Computed tomography (CT) was performed and it showed left posterior cerebellar infarction in late acute clinical phase, without haemorrhage. The patient underwent angiography that excluded cerebral artery dissection but showed acute occlusion of posterior internal cerebral artery. Echocardiogram showed moderate left ventricular hypertrophy with normal global and segmental kinetics, left atrial dilatation; besides, left ventricular apical thrombus was excluded. Holter ECG monitoring showed very frequent polymorphic ventricular and supraventricular extrasystolic beats. Urinary metanephrines were markedly increased. In particular urinary normetanephrine was up to 9 times the upper limit of normality (4874 ug/L, normal range 162-527 ug/24 h). Since the surgical intervention was always refused, this case is a rare documentation of the several different cardiovascular clinical manifestation due to catecholamine secretion in a single patient. Paraganglioma could be a catecholamine secreting tumour that arises from cromaffin tissue of the sympathetic nervous system. Clinical manifestations of paraganglioma are extremely variable leading to its designation as "great mimic". Adrenal tumours are associated with several cardiovascular diseases including LV hypertrophy, myocardial infarction, cardiac arrhythmias, heart failure and Tako Tsubo cardiomyopathy. Cerebral accident is a rare manifestation of adrenergic crisis with several possible aetiologies such as vasospasm or cardioembolic events. In our clinical case, considering the type and localization of the cerebral ischemic injury, the stroke is likely to have a cardioembolic etiology. Apical left ventricular trombus and PFO were excluded. Therefore, in view of left atrial enlargement and the frequent supraventricular ectopy, even in the absence of documented arrhythmia, an undiagnosed episode of catecholamines induced atrial fibrillation was suspected, with subsequent cardioembolic event. Abstract P257 Figure.

Transcatheter closure of atrial septal communication: Impact on quality of life in mid-term follow-up.

Atrial septal defect (ASD) and patent foramen ovale (PFO) are specific types of atrial septal communications (ASC). We aimed to assess quality of life (QoL) in patients before and after percutaneous closure of ASC and determine the factors influencing QoL in this group of patients. We performed a clinical assessment and conducted an SF-36 questionnaire, electrocardiography and echocardiography studies in patients before and 6 months after percutaneous ASC closure. Patients with ASD (n = 56) had a lower SF-36 total score than those with PFO (n = 73), before and after percutaneous ASC occlusion (both p < 0.001). After the procedure, the improvement of SF-36 total score in patients with ASD or atrial fibrillation was greater (p < 0.001 and p = 0.005, respectively). We observed correlations between improvement of QoL and baseline supraventricular extrasystolic beats (rs = 0.28; p = 0.002), but not ventricular extrasystolic beats (rs = 0.03; p = 0.76). Quality of life improvement was predicted in patients with ASD by higher baseline tricuspid annular plane systolic excursion (TAPSE) and right ventricular longitudinal dimension R2 = 0.38; p < 0.001. However, in patients with PFO, this was predicted by TAPSE, lack of arterial hypertension and usage of angiotensin-converting enzyme inhibitors, R2 = 0.30; p < 0.001. Patients with ASD have lower QoL than those with PFO before and after percutaneous ASC occlusion. Six months after the procedure, the improvement of QoL in patients with ASD was higher than in those with PFO. The change in QoL self-assessed by patients after the procedure was associated with episodes of arrhythmia and was predicted with echocardiographic and clinical parameters.

Transcatheter closure of atrial septal communication: impact on P-wave dispersion, duration, and arrhythmia in mid-term follow-up.

Atrial septal communications (ASCs) include atrial septal defects (ASDs) and patent foramen ovale (PFO). The purpose of this study was to assess P-wave dispersion (PWD) and the prevalence of arrhythmia in patients before and after ASC closure. We analysed the clinical history and performed 12-lead electrocardiograms, echocardiograms, and 24-h Holter electrocardiograms in patients with ASC, before and six months after ASC closure. We included patients with ASD (n = 56) and PFO (n = 73). PWD before percutaneous ASC closure was predicted by right ventricular outflow tract (RVOT) proximal diameter, left atrial area, ASD, smoking, and paroxysmal dyspnoea, R2 = 0.67; p < 0.001. RVOT proximal diameter was an independent predictor of PWD, both in patients with ASD and PFO. Six months after successful closure of ASC, a reduction in PWD was observed in the whole group of patients as well as in patients with ASD and PFO considered separately. A decrease in PWD was associated with reduction of maximum P-wave duration. At the same time, in the whole group, we noticed a reduction in the number of supraventricular and ventricular extrasystolic beats and fewer atrial fibrillation (AF) episodes, p < 0.04 for all variables. Postprocedural AF episodes in patients with ASD were predicted by PWD of 80 ms. Percutaneous closure of ASC is associated with a reduction of PWD and fewer arrhythmia episodes six months after the procedure. PWD predicts AF episodes after ASD closure.

Impact of radiofrequency catheter ablation on echocardiographic and cardiopulmonary performance in patients with ventricular extrasystolic beats and suspected arrhythmia-induced cardiomyopathy

Integrated backscatter intravascular ultrasound (IB-IVUS) is a useful method for analyzing coronary plaque tissue. We evaluated whether tissue composition determined using IB-IVUS is associated with the progression of stenosis in coronary angiography. Sixty-three nontarget coronary lesions in 63 patients with stable angina were evaluated using conventional IVUS and IB-IVUS. IB-IVUS images were analyzed at 1-mm intervals for a length of 10 mm. After calculating the relative areas of the tissue components using the IB-IVUS system, fibrous volume (FV) and lipid volume (LV) were calculated through integration of the slices, after which percentages of per-plaque volume (%FV/PV, %LV/PV) and per-vessel volume (%FV/VV, %LV/VV) were calculated. Progression of coronary stenosis was interpreted from the increase in percent diameter stenosis (%DS) from baseline to the follow-up period (6–9 months) using quantitative coronary angiography. %DS was 24.1 ± 12.8 % at baseline and 23.2 ± 13.7 % at follow-up. Using IB-IVUS, LV was 31.7 ± 10.5 mm3, and %LV/PV and %LV/VV were 45.6 ± 10.3 % and 20.2 ± 6.0 %, respectively. FV, %FV/PV, and %FV/VV were 35.5 ± 12.1 mm3, 52.1 ± 9.5 %, and 23.4 ± 7.1 %, respectively. The change in %DS was −0.88 ± 7.25 % and correlated closely with %LV/VV (r = 0.27, P = 0.03) on simple regression. Multivariate regression after adjustment for potentially confounding risk factors showed %LV/VV to be correlated independently with changes in %DS (r = 0.42, P = 0.02). Logistic regression analysis after adjusting for confounding coronary risk factors showed LV (odds ratio 1.08; 95 % confidence interval 1.01–1.16; P = 0.03) and %LV/VV (odds ratio 1.13; 95 % confidence interval 1.01–1.28; P = 0.03) to be independent predictors of the progression of angiographic coronary stenosis. Our findings suggest that angiographic luminal narrowing of the coronary artery is likely associated with tissue characteristics. IB-IVUS may provide information about the natural progression of luminal narrowing in coronary stenosis.

Incidental myocardial mass: differential diagnosis, clinical approach and literature review

A 30-year-old male was evaluated in our hospital for the presence of transient palpitations. The ECG showed sporadic ventricular extrasystolic beats with normal ventricular depolarization and repolarization phases. Two-dimensional transthoracic echocardiography demonstrated a localized intraventricular myocardial mass (measuring 3 x 2 mm) in the basal lateral wall. To further characterize the mass, the patient was addressed to cardiac magnetic resonance imaging (MRI). Noninvasive myocardial tissue characterization with T2-weighted sequences (with and without fat suppression), and T1-weighted after contrast suggested the presence of fat tissue associated with undiversified muscle tissue. The intramyocardial mass was not capsulated and partially infiltrated the surrounding myocardium. The imaging features suggested the diagnosis of a benign myocardial mass with mixed aspects between cardiac hamartoma and lipoma. To monitor mass growth and in the absence of new symptoms, the patient is followed up yearly with transthoracic echocardiography, and with cardiac MRI exams every 3 years. This case highlights the utility of cardiac MRI to assess a myocardial mass noninvasively and delineate its anatomy and tissue characterization, which potentially avoids myocardial biopsy.

Novel insights into the role of the sympathetic nervous system in cardiac arrhythmogenesis

It has long been recognized that increased sympathetic nerve activity during physiologic stress (exercise, swimming, emotion, arousal, loud noise, etc.) has profound influences on the electrical and contractile functions of the heart. In the severely predisposed heart, these stressors may lead to ventricular tachyarrhythmias and sudden death. Still little is known about the temporal relationship between instantaneous autonomic nerve activity and arrhythmias. There is a large variety of autonomically-driven arrhythmias, from serious ventricular tachycardia in pathological conditions to single supraventricular and ventricular extrasystolic beats in the healthy heart. The latter are considered harmless if occurring at low frequency. In the atria, mounting data indicate the presence of a sophisticated network of ganglionated plexi with major influences on cardiac function. The ablation of multiple such ganglia can suppress pulmonary vein potentials and atrial fibrillation. At the cellular level, recent studies have focused on the spatiotemporal details of cyclic nucleotide signaling influencing ion channel function during neurohumoral stimulation. We have come to understand that sarcolemmal ion channels and other electrogenic transporters are macromolecular complexes that interact with structural elements (other than the phospholipid bilayer) to promote regionalization and targeting by regulatory proteins. Compartmentation of these regulatory proteins in subdomains of the myocyte is increasingly recognized and thought to segregate the functional (including electrogenic) responses induced by different neuromediators and hormones. In this article, contemporary issues are discussed regarding arrhythmias that are triggered by influences from the neurocardiac interface, covering the field from the molecular genetic to the intact integrated level. Actual questions are listed per topic, and viewpoints are expressed.

10.1 Sympathetic Responses to Ventricular Extrasystolic Beats in Obese Subjects without and with Sleep Apnoea

10.1 Sympathetic Responses to Ventricular Extrasystolic Beats in Obese Subjects without and with Sleep Apnoea

Maintained normalization of cardiovascular dysfunction 5 years after parathyroidectomy in primary hyperparathyroidism

Primary hyperparathyroidism (pHPT) has been associated with premature death in cardiovascular diseases. Short-term prospects for normalization of cardiovascular derangements have been described after parathyroidectomy. This study explores long-term effects of parathyroidectomy on cardiovascular functions in pHPT. Thirty consecutive patients with pHPT were reexamined 1 and 5 years after parathyroidectomy, together with 30 matched controls, with echocardiography and a bicycle exercise test. Serum calcium was normal in all patients and control subjects at follow-up. The maximal blood pressure during the exercise was higher before parathyroidectomy (median 223 [range, 200-268] mm Hg vs 202 [165-277] mm Hg, P < .05) but not 5 years after (230 [155-270] mm Hg vs 219 [165-252] mm Hg. The ST-segment depression diminished from -1.4 (-8.3-0) to -0.8 (-3.3-0) mm 1 year after parathyroidectomy and further to -0.1 (-3.3-0.0) mm after 5 years but was unchanged in the control group. The number of ventricular extrasystolic beats at exercise testing in the pHPT group before parathyroidectomy was higher than in the control group (1 [0-340] vs 0 [0-3]). The isovolemic relaxation time at rest was prolonged before parathyroidectomy (mean 100 +/- 17 ms [SD] vs 89 +/- 14 ms, P < .05). Parathyroidectomy can induce long-lasting improvement in regulation of blood pressure, left ventricular diastolic function, cardiac irritability (ventricular extrasystolic beats), and other signs of myocardial ischemia, with potential implications for the postoperative life expectancy of patients with pHPT who have undergone parathyroidectomy.

Baseline reconstruction for localization of rapid ventricular tachycardia from body surface potential maps

Determination of an accurate electrocardiographic (ECG) baseline is generally needed for localization of ventricular arrhythmias with body surface potential mapping (BSPM). We suggest a novel signal processing method for ECG baseline reconstruction during monomorphic ventricular tachycardias (VT). The method is based on an assumption that VT consists of similar ventricular extrasystolic beats with overlapping depolarization and repolarization. The sequential reconstruction algorithm utilizes information of small variations in the heart rate and yields a non-overlapping QRST-signal, provided that the measurement set-up has a high enough temporal resolution to avoid distortions due to sampling differences and misalignment of individual beats. The reconstructed QRST-signal is utilized to subtract overlapping T-waves from the QRS complexes during VT. The use of the method is demonstrated with clinically measured BSPM data.

Left ventricular systolic and diastolic function and exercise testing in primary hyperparathyroidism—effects of parathyroidectomy

Background. Nontraditional manifestations of primary hyperparathyroidism (HPT) are controversial and may include morbidity, mortality, and risk factors for cardiovascular diseases. This study evaluates cardiovascular functions at rest and during exercise in HPT. Method. Thirty patients with HPT (mean serum calcium, 2.97 ± 0.24 mmol/L) and 30 control people with normocalcemia, matched for age and sex, underwent symptom-limited exercise testing and echocardiography before and 13 months (mean) after having a parathyroidectomy. Results. Despite similar maximal workload and blood pressures at rest in patients and healthy controls, HPT associated with higher systolic blood pressure during exercise (P =.03) and increased number of ventricular extrasystolic beats (P =.04). There was also an operatively reversible increase in ST-segment depression during exercise. Echocardiography showed an increased left ventricular (LV) isovolemic relaxation time (P =.02) and mitral deceleration time (P =.08), which indicate an LV diastolic dysfunction that could be partially reversed by operation. LV systolic function (ejection fraction and shortening fraction) tended to be elevated in HPT (P =.07 and.06, respectively) and diminished after parathyroidectomy. There was a trend toward higher LV mass, especially among the men with HPT (P =.06), which was unchanged postoperatively. Conclusions. HPT couples to reversible signs of myocardial ischemia and LV dysfunctions with a possible increased risk of life-threatening arrhythmia. (Surgery 2000;128:895-902.)

Prospective study of autonomic nerve function in type 1 and type 2 diabetic patients: 24 hour heart rate variation and plasma motilin levels disturbed in parasympathetic neuropathy.

To clarify the impact of autonomic neuropathy in diabetic patients, we have conducted a prospective study of 58 Type 1 and 51 Type 2 diabetic patients (investigated at baseline, after 4, and after 7 years). In Type 1 diabetic patients, the sympathetic nerve function (orthostatic acceleration and brake indices) and in Type 2 patients, parasympathetic nerve function (R-R interval variation; E/l ratio) deteriorated during 7 years of prospective observation. Symptoms of autonomic neuropathy were associated with signs of autonomic neuropathy (low brake indices) in Type 1 but not in Type 2 diabetic patients. In the latest assessment 24 h ECG recording was performed and blood samples assayed for neuropeptide Y (NPY) and motilin were obtained. Type 1 diabetic patients with parasympathetic neuropathy (abnormal E/l ratio) showed significantly lower SD value (less variation in the R-R intervals; 29 [17] vs 50 [16], [mean (interquartile range)]; p = 0.001) and higher postprandial plasma motilin values (70 [20] pmol l-1 vs 50 [15] pmol l-1; p < 0.01) than patients with normal parasympathetic nerve function. In Type 2 diabetic patients, sympathetic neuropathy (low brake indices) was associated with an increased frequency of ventricular extra systolic beats during 24 h ECG recording (rs = 0.65; p < 0.01). Postprandial plasma NPY levels were not associated with disturbed autonomic nerve function.

MUSCLE AND SERUM MAGNESIUM IN PULMONARY INTENSIVE CARE UNIT PATIENTS

Muscle specimens by means of quadriceps femoris needle biopsy and blood samples were obtained in 32 patients consecutively admitted to a pulmonary ICU for chronic obstructive pulmonary disease and acute respiratory failure, and in 30 age and sex-matched healthy control subjects. Muscle magnesium (Mg) and potassium (K) content was assessed by atomic absorption spectrophotometry; serum electrolytes were also measured. The presence of clinical and biochemical correlates of low serum and muscle Mg was investigated. Three (9.4%) out of 32 patients had hypomagnesemia (Mgs less than or equal to 0.7 mmol/L) with normal muscle Mg values, whereas low muscle Mg values were found in 15 (47%) of 32 patients, with no alterations of serum Mg levels. Muscle Mg was decreased significantly in pulmonary ICU patients as compared to control subjects. No significant correlation was present between serum and muscle Mg, or between serum and muscle K. Significant relationships between muscle Mg and both muscle and intracellular K concentrations were also found. Lower values for muscle and intracellular K and a higher incidence of both more prolonged ICU stays and ventricular extrasystolic beats characterized the ICU patients with altered muscle Mg levels. We conclude that, given the serious complications of Mg metabolism derangements, the presence of altered cell Mg content should be taken into account in pulmonary ICU patients. Moreover, in these patients, serum Mg levels are of little value in the diagnosis of intracellular Mg deficits.

Fever and Cardiac Rhythm

To study the effect of fever on cardiac rhythm and conduction, we recorded 24-hour electrocardiograms in 27 young men during an uncomplicated acute febrile infection (12 patients had adenovirus, four had influenza, three had Mycoplasma pneumoniae, and eight were undefined) and after recovery. During the first 24-hour recording period, the mean axillary temperature in the whole group was 38.4 degrees C. The mean heart rate during the febrile period was 84.0 beats per minute. After recovery, it was 66.5 beats per minute. When the temperature rose by 1 degree C, the heart rate increased on the average by 8.5 beats per minute. During the febrile period, the heart rate remained high, even during sleep. The PR interval shortened significantly at a heart rate of 60 beats per minute and occasional first- or second-degree atrioventricular blocks were rarer. The QT interval shortened significantly at heart rates of 60, 80, and 100 beats per minute. Simple and complex ventricular extrasystoles were not increased by fever. In contrast, frequent supraventricular extrasystoles developed in two patients during high fever, but not during the control recording. If an acute febrile infection induces a prolongation of the atrioventricular conduction or the QT interval, or if frequent ventricular extrasystolic beats are triggered, complications must be suspected.

Concealed Extrasystolic Ventricular Bigeminy with Interpolation

The first reported case of concealed extrasystolic ventricular bigeminy with interpolation is described. This arrhythmia is characterized by the presence of both interpolated ventricular extrasystolic beats and a presumed persistent and continuous bigeminal ectopic rhythm with exit block. The distributional pattern of sinus conducted beats in the present case conforms to a formula defining this unusual disorder of rhythm, while the appearance of manifest ectopic beats follows the rule of bigeminy.

Phasic coronary arterial flow velocity during arrhythmias in man

The influence of cardiac arrhythmias on coronary arterial flow velocity studied by means of a Doppler catheter flowmeter system is described in 47 patients. The arrhythmias examined included atrial and ventricular extrasystoles, atrial fibrillation, pacemaker-induced atrial tachycardia, paroxysmal atrial tachycardia, ventricular tachycardia, Wenckebach second degree atrioventricular block and complete heart block. In atrial and, less frequently, in ventricular extrasystolic beats, peak coronary arterial flow velocity did not change significantly when the preceding R-R interval was greater than 0.50 second. However, when this interval was shorter than 0.50 second, a proportional decrease in peak coronary arterial flow velocity occurred. Variations in beat to beat coronary arterial flow velocity were seen uniformly in patients with atrial fibrillation. However, there was no correlation between peak coronary arterial flow velocity and the preceding R-R interval; in addition, no correlation was found between peak coronary arterial flow velocity and the same cycle length. In pacemaker-induced atrial tachycardia, decreased peaked coronary arterial flow velocity was observed at pacing rates greater than 140/min. In 1 patient with paroxysmal atrial tachycardia with an atrial rate of 200/min, there was a marked decrease and irregularity in coronary arterial flow velocity. The more abrupt decrease in flow velocity occurred in ventricular tachycardia. In Wenckebach second degree atrioventricular block, no measurable coronary arterial flow velocity was observed in the cycle encompassed by the dropped beat. However, the total area under the velocity curve was greater in the pre-dropped atrial beat than in other beats. In patients with complete heart block, the systolic component of flow velocity was greater than in patients in sinus rhythm.

Circulatory support by a left ventricular balloon pump.

The ability of a left ventricular balloon pump to provide support of the circulation when myocardial function had been severely impaired was examined in six dogs. When the unassisted damaged left ventricle could not maintain systemic blood flows adequate for survival, left ventricular balloon pumping resulted in peripheral blood flows which ranged from 37 to 77 ml/min/kg. These balloon-generated blood flows have been maintained for periods up to three hours. Assist of the circulation by balloon pumping was accompanied by an increase in systemic arterial blood pressure and a decrease in left atrial end-diastolic pressure. The effectiveness of left ventricular balloon pumping was reduced in hypovolemia and in the presence of ventricular extrasystolic beats. Left ventricular balloon pumping was not effective in generating a sustained peripheral flow of blood when the heart was fibrillating.