The veins of the left ventricular summit in patients undergoing cardiac resynchronization therapy

Introduction

While the coronary sinus and its left ventricular branches have been extensively described, the veins of the left ventricle summit (LVS) have been much less studied. The emergence of new ablation techniques for ventricular tachycardias, which make use of the LVS veins, has generated a renewed interest in the anatomy of these venous conduits.

Purpose

The aim of the study was to describe in detail the anatomy of the LVS veins using rotational venous angiography.

Material and methods

All patients (N=106, age 68±12 years, 72 men) underwent coronary venous angiography during the cardiac resynchronization implant procedures.

Results

The LVS veins identified were the great cardiac vein (GCV), the anterior interventricular vein (AIV) and the mitro-aortic LVS vein (MALVSV). The MALSV emerged from the GCV between 12 and 2 o'clock on the mitral ring, coursed inside the left atrioventricular groove, towards the aorto-mitral continuity (AMC), where it turned towards the ventricular septum and coursed parallel to the AIV, tapered down and ended at midventricular level. Most of the course of this vein was in the region of the LVS. The diameter of the venous conduit at the GCV-AIV junction was 4.9±1.0 mm. The MALVSV was present in 76 patients (72%; Figure 1). The MALVSV diameter was 2.4±0.6mm at the ostium (Figure 2) and 1.8±2.0 mm at the AMC. The takeoff angle was 134±27°. The total length of the vein was 34±16 mm, of which 23±14mm were inside the AV groove and 11±9mm, were along the ventricular septum. The length of the MALSV segment embedded in the left AV groove as well as the total length of MALSV correlated significantly with the left atrial diameter (r=0.44; P=0.040 and r=0.45; p=0.016 respectively) as well as with the right ventricular systolic pressure (r=0.50; p=0.028 and r=0.57; P=0.030 respectively).

Conclusions

This study brings new insights into the angiographic anatomy of the LVS veins. Detailed knowledge of these venous tributaries could help with the development of new strategies for ablation of LVS tachycardias.

Funding Acknowledgement

Type of funding sources: None.

Left ventricular longitudinal contraction impacts the left atrial appendage function and the occurrence of thromboembolic events in patients with atrial fibrillation

Introduction

Previous research has revealed a relationship between left ventricular (LV) function and incidence of stroke in atrial fibrillation (AF) but the mechanism remains unknown.

Purpose

Given that the left atrial appendage (LAA) is located in the vicinity of the LV base we hypothesized that the LV longitudinal contraction has an impact on the LAA function, LAA thrombus (LAAT) formation, and occurrence of ischemic stroke (Figure 1A). The aim of this study was to investigate this phenomenon using transesophageal echocardiography (TEE).

Material and methods

We included in our study 105 consecutive patients (age 59±11; 55 men) undergoing TEE-guided cardioversion for AF. LV longitudinal function was assessed using the mitral annulus plane systolic excursion (MAPSE). LAA function was evaluated using the LAA emptying velocity (LAAEV) and LAA ejection fraction (LAAEF) (Figure 1B). The presence LAAT and spontaneous echo contrast (SEC) were evaluated as well.

Results

Our patients had a median CHADS2vasc score = 3 (IQR 2–4), LVEF=50±11%, and MAPSE=7.3±1.7mm. MAPSE showed a positive significant correlation with both LAAEV (r=0.34; p<0.01) and LAAEF (r=0.23; p<0.05) (Figure 2). LVEF correlated significantly with LAAEV (r=0.42, p<0.01), and LAA area (r=−0.34; p<0.05), respectively. Additionally, patients who exhibited SEC had significantly lower LAAEF as well as LAAEV when compared with patients without SEC: 31±12% vs 38±12% P=0.022 and 35±18cm/s vs 49±21cm/s P=0.005. Patients who displayed both SEC and LAAT had wider LAA neck when compared to the rest of the group (21.46±3.96mm vs. 18.23±3.78mm; P=0.021). Logistic regression analysis revealed that MAPSE independently predicted the occurrence of ischemic stroke both in univariate and multivariate models that also included the CHADSvasc2 score.

Conclusions

LV longitudinal contraction appears to influence LAA function. This relationship could potentially have an impact on occurrence of thromboembolic events in patients with atrial fibrillation.

Funding Acknowledgement

Type of funding sources: None.

Catheter ablation with ethanol infusion in the vein of marshall for persistent atrial fibrillation: safety and procedure duration

Funding Acknowledgements

Type of funding sources: None.

Background

Ethanol Infusion in the Vein of Marshall (EIVOM) has been recently introduced as an efficient technique that helps achieving mitral isthmus block during ablation procedures for persistent atrial fibrillation (PAF) or peri-mitral atrial flutter.

Purpose

We have evaluated the safety of EIVOM and the duration required to perform this procedure. 

Methods 

We performed EIVOM in 121 patients for PAF (mean age of 65 years (range 40-83, 73% men; Mean EF 50%. The main steps of the EIVOM were as follows: the procedure commenced with catheterization of the coronary sinus, followed by the subsequent introduction of an angiography catheter that allowed for iodine contrast injection and vein of Marshall (VOM) localization, 1.5-2.5 mm angioplasty balloon over 0.014" guidewire placement and finally the ethanol injection up to 10 ml. 

Results

No major complications were observed during the ablation procedure or before hospital discharge.

In 62 patients in whom procedure duration data was available the mean EIVOM procedure time was 41 min (range from 13 to 105 min).

After the first 20 procedures, where the learning curve for the operators has to be taken into consideration, a reduction in the time required to achieve EIVOM was consistently noted, with an average of less than 30 min. and for the last 20 procedures less than 20 min. Factors which increase the time required for successful EIVOM include: difficulty in visualizing the ostium of the VOM, a VOM ostium located proximally, difficulty in advancing the angioplasty wire into the VOM and balloon displacement and repositioning.

Conclusions

Ethanol infusion in the Vein of Marshall is a safe and efficient technique that can be performed in an acceptable amount of time after an initial learning curve. Abstract Figure. Image 1 VOM

Usefulness of the angiographic anatomy of the vein of marshall for ablation procedures for persistant atrial fibrillation

Funding Acknowledgements

Type of funding sources: None.

Background

Ethanol Infusion in the Vein of Marshall (EIVOM) was recently proposed as an efficient adjunctive technique for obtaining mitral isthmus block during catheter ablation for persistent atrial fibrillation. 

Purpose

Given these considerations the objective of this research was to delineate the angiographic anatomy of the Vein of Marshall (VOM). 

Methods

Fluoroscopy images were obtained retrospectively in 124 patients with persistent atrial fibrillation who underwent coronary sinus angiography for EIVOM (96 patients) or cardiac resynchronization implant (18 patients). The measurements were performed using Osirix DICOM reader using the known diameter of the angiographic catheter for calibration. The distance between the ostium of the coronary sinus (CS) and the ostium of the VOM was measured in the anteroposterior view. Additionally, the angle at which the ostium of VOM opens in the CS was obtained. 

Results

The diameter of the VOM ostium was 1.8 ± 0.6mm. The length of the VOM was 18.6 ± 9.1mm. The distancebetween the CS ostium and VOM ostium was as follows: less than 10mm for 1 patient (1%), between 11-20mm for 10 patients (10.41%), between 21-30mm for 38 patients (39.58%), 31-40mm for 31 patients (32.29%), between 41-50mm for 15 patients (15.62%) and >50mm for 1 patients (1%) (53mm). 

The average takeoff angleof the VOM from the CS between the main branch of the VOM and the CS was measured at 140 degrees (range 90-175 degrees). No correlation could be made between the takeoff angle and the distance between CS ostium and VOM ostium. 

In the group of patients undergoing cardiac resynchronization the takeoff angle from the CS was 153°±17° and it correlated significantly with the left ventricular systolic diameter and the left ventricular ejection fraction determined by echocardiography(r = 0.52; p = 0.008 and respectively r = 0.50; p = 0.009).

Conclusions

Understanding the anatomy of the Vein of Marshall (VOM) is crucial in helping operators efficiently exploit the therapeutic potential of ethanol injection after accurate localization of such an important branch of the left atrial venous system. Abstract Figure. 1 Fig 1 Angle CS-VOM

Achieving acute mitral isthmus block with catheter ablation with vein of marshall ethanol infusion

Funding Acknowledgements

Type of funding sources: None.

Background

Achieving bidirectional mitral isthmus block during radiofrequency (RF) ablation for persistent atrial fibrillation (AF) is still challenging. The conventional ablation method involves RF applications on the endocardial aspect of the Mitral Isthmus (MI), and for a majority of patients, in the distal coronary sinus (CS). 

Purpose

We have evaluated the acute success of obtaining mitral isthmus block by adding another epicardial component using ethanol infusion in the vein of Marshall (EIVOM) in addition to endocardial MI and epicardial CS ablation. 

Methods 

We studied 121 patients (pts.) with a mean age of 65 years (range 40-83) 73% men; 119 with longstanding persistent AF (98%) and 2 with perimitral flutter (2%). The mean duration of AF was 53 months (12-244 months). In the majority of patients, additional endocardial (on the ventricular aspect of the MI) and/or epicardial (distal CS) (RF) ablation was performed in order to achieve MIB. The ablation procedure was performed under general anesthesia (GA) for 81 pts (67%). EIVOM was perform with a mean 6 ml ethanol (range 2-10ml) 

Results

 Bidirectional MIB was obtained in 114 pts. (94,2%). The 7 patients without MIB were scheduled for another ablation procedure (4 pts under GA during the first procedure). The average RF delivery time to block was 160 seconds (range 42-480 seconds) for the endocardial MI RF ablation (point-by-point application with a power of 50W and an Ablation Index of 450-500, contact force 10-20g) and 156 seconds (range 55-438) for the epicardial MI RF ablation (applications with a power of 20W). Bidirectional endocardial and epicardial MIB was confirmed by conventional pacing maneuvers performed in sinus rhythm. No major complications were observed. The parameters associated with failure for MIB were AF duration, Left Atrial dilatation >200 ml, MI thickness (epicardial endocardial distance on the CARTO maps >15mm).

Conclusion

Ethanol infusion in the vein of Marshall is a safe approach and is associated with a higher success rate of obtaining acute bidirectional endocardial and epicardial mitral isthmus block when compared with the conventional method. Abstract Figure. Bloc Mitral Endo; Bloc Mitral Epi;

QRS voltage in precordial leads in patients with neurally mediated syncope

Background

We have previously demonstrated that patients with neurally mediated syncope (NMS) who have an isolated QRS complex, of very low voltage (≤0.3mV cutoff), in one of the frontal leads on the 12-lead electrocardiogram have a threefold increase in the risk of syncope recurrence. The potential relationship between isolated low voltage (ILV) in precordial leads (Figure A) and recurrent NMS has not been yet explored.

Purpose

To prospectively evaluate whether the presence of ILV in the precordial leads predicts recurrence of NMS.

Methods

We included 135 patients with NMS (age 49±20) years, with a median of 4 syncopal episodes. During a median period of 15 months, 43 patients (32%) experienced recurrent syncope. The lowest QRS voltage (QRSmin) was determined separately for the frontal and precordial leads. The cutoff for precordial QRSmin that best discriminated between patients with recurrent and no recurrent syncope was ≤0.7mV (ROC curve AUC=0.65).

Results

Isolated low voltage in precordial leads was present in 49 (36%) of patients. The lead which displayed QRSmin in the precordial leads was V1 in 35 (71%) patients. The actuarial total syncope recurrence rate at 1 year was 26% (95% CI 16–42%) in patients with ILV in precordial leads, and 21% (95% CI 6–39%) in patients without ILV (log rank test P=0.043; Figure B). The significant relationship between the presence of ILV in precordial leads and syncope recurrence was retained in Cox multivariate analysis that included isolated very low voltage in frontal leads (≤0.3mV cutoff), as well as the number of syncopal episodes.

Conclusions

Isolated low QRS voltage in the precordial leads predicts recurrence of NMS independent of isolated low QRS voltage in the frontal leads.

Figure 1

Funding Acknowledgement

Type of funding source: None

P2466The impact of circumferential pulmonary vein isolation on global and regional left atrial function in patients with paroxysmal atrial fibrillation

Introduction

The effect of circumferential pulmonary vein isolation (PVI) for atrial fibrillation (AF) on left atrial (LA) function has not been well defined.

Purpose

The aim of this study was to evaluate the immediate impact of ablation on parameters of global and regional LA function using intracardiac echocardiography (ICE)

Methods

We studied 26 consecutive patients (age 56±10 years, 19 men) with paroxysmal AF using ICE before and immediately after circumferential PVI. All pulmonary veins were isolated in all patients. ICE measurements included LA fractional area shortening, peak A wave on transmitral Doppler flow, peak emptying velocity on the left atrial appendage (LAA) Doppler flow, as well as tissue Doppler myocardial velocities at the level of the posterior LA wall, interatrial septum, and lateral wall, which were used as parameters of regional LA function.

Results

The mean radiofrequency ablation time was 37±22min. Post ablation there was a significant reduction of the LA fractional area shortening from 27±8% to 22±6% (p<0.01). The tissue Doppler velocity of atrial contraction at the posterior wall decreased significantly post ablation: from 8.9±1.8 cm/s to 6.9±1.4 cm/s (p<0.01). There were no significant differences between the pre and post ablation values for tissue Doppler velocities at the level of the interatrial septum or LA lateral wall. The post ablation peak transmitral A wave and peak LAA Doppler velocities did not differ significantly from the pre ablation values.

Conclusion

In patients with paroxysmal atrial fibrillation, circumferential PVI results in an immediate decrease in LA function without a significant change in LAA function.

Troponin T elevation after implanted defibrillator discharge predicts survival

BACKGROUND

Cardiac troponin T (cTnT) elevations have been reported to occur after implantable cardioverter-defibrillator (ICD) discharges, but their prognostic significance is unknown.

OBJECTIVE

To evaluate whether cTnT elevations occurring after ICD discharges have an impact on survival.

DESIGN

Prospective observational study.

PATIENTS

174 patients (mean (SD) age 68 (12) years, 32 women) who received spontaneous (n = 66) or induced (n = 108) ICD discharges were studied. The mean (SD) left ventricular ejection fraction was 29 (11)%.

MAIN OUTCOME MEASURES

Troponin T was measured between 12 and 24 h after ICD discharge. Patients received between 1 and 19 discharges (mean (SD) 2.4 (2.4)), with total delivered energy ranging from 6 to 288 J (mean (SD) 41 (63) J). The relationship between cTnT levels and all-cause mortality was assessed in univariate and multivariate analyses.

RESULTS

During a median follow-up period of 41.8 months (range 3-123), 56 patients died. Patients with a post-discharge cTnT level of >/=0.05 ng/ml had worse survival than those with cTnT <0.05 ng/ml. The significant relationship between raised cTnT and survival was retained in Cox multivariate analysis adjusted for total ICD energy delivered during an arrhythmia episode, age, sex, presence of coronary artery disease, left ventricular ejection fraction and serum creatinine.

CONCLUSIONS

Elevation of troponin T after ICD discharge, even when it occurs after device testing, is a risk factor for mortality that is independent of other common clinical factors that predict survival in such patients.

Abnormalities of left ventricular long-axis function predict the onset of hypertension independent of blood pressure: a 7-year prospective study

Increased blood pressure and left ventricular (LV) mass predict the onset of the clinically manifest hypertension, but little is known regarding the possible predictive value of LV function. The present study was designed to evaluate the association between echocardiographic LV long-axis systolic, and diastolic function and hypertension onset. We prospectively followed 244 normotensive adults with a family history of hypertension (HTN), with echocardiography for 7 years. M-mode derived atrioventricular plane displacement of the mitral and tricuspid annuli (MAVPD and TAVPD respectively), and LV circumferential fractional shortening were calculated. Diastolic function of the left and right ventricle were assessed using Doppler indices of the mitral and tricuspid inflow. During follow-up, 79 subjects developed hypertension (H group) and 165 subjects remained normotensive (N group). H group subjects had diminished MAVPD (13.8+/-3.4 vs 15.0+/-3.1 mm; P=0.007), lower mitral E/A ratio, and longer mitral E-wave deceleration time as compared to N group. In multivariate Cox model MAVPD and mitral E/A ratio predicted the onset of hypertension independent of LV mass index, blood pressure, pre-hypertensive status at baseline, age, sex and body mass index. During follow-up, H subjects experienced a significant decline in MAVPD and mitral E/A ratio, whereas the indices of right ventricular function and LV circumferential shortening remained intact. In conclusion, alterations in LV long-axis systolic and diastolic function, as measured by MAVPD and E/A ratio predict the onset of hypertension. These parameters declined during the development of hypertension.

Risk of asymptomatic and symptomatic gallstones in moderately obese women: a longitudinal follow-up study

Obesity is a rather documented risk factor for the formation of gallstones (GS) in women. The magnitude of the increased risk and the rates of GS occurrence, however, have not been well quantified, except for two studies on the risk of symptomatic stones in obese women. We analyzed the incidence of GS in 157 moderately obese women (body mass index, 31.4 +/- 3.6 kg/ m2) followed up prospectively by ultrasound for 2-6 yr (mean 3.95 yr). Women with morbid obesity (body mass index > 40 kg/m2) were excluded from the study, as well as patients having diseases with lithogenic risk. All the enrolled women had normal cholecystosonogram results at the beginning of the study. Age, family history of GS or obesity, parity, age of obesity onset, hyperlipoproteinemia type, plasma cholesterol (total, HDL, LDL), and triglycerides were assessed. The Student's t, the Mann-Whitney rank sum and the Fisher's exact tests were used, as well as the multiple logistic regression for the multivariate analysis. During the survey, 16 of 157 women (10.2%) developed GS. GS were asymptomatic in 11 persons (68.8%). The cumulative incidence of both asymptomatic and symptomatic GS was 2.6 cases/100 obese women.year. During the follow-up, most of the detected GS were asymptomatic, and this explains the higher GS incidence rate found compared with that previously calculated for symptomatic GS. The following risk factors were associated with GS formation: age (p = 0.002), family history of GS (p = 0.011), early obesity onset (p = 0.003), and hyperlipoproteinemia type IV (p = 0.011). A high risk class might be thus identified among obese women, offering a more realistic approach for the primary prophylaxis of GS.

Additive value of thallium single-photon emission computed tomography myocardial imaging for prediction of perioperative events in clinically selected high cardiac risk patients having abdominal aortic surgery

The present study was designed to prospectively evaluate whether reinjection thallium-201 single-photon emission computed tomography (SPECT) has a significant additive predictive value for occurrence of perioperative cardiac events in clinically selected patients at high cardiac risk undergoing abdominal aortic surgery. Of a group of 517 consecutive patients referred, 134 had > or = 2 of the following clinical or electrocardiographic cardiac risk variables: age > 70 years; history of myocardial infarction, angina, or congestive heart failure; diabetes mellitus; hypertension with severe left ventricular hypertrophy; and Q waves or ischemic ST-segment abnormalities on electrocardiogram at rest. Operation was performed after thallium SPECT study. Twelve patients (9%) had major perioperative events (cardiac death or nonfatal myocardial infarction) and 18 patients had other cardiac events (unstable angina, congestive heart failure, or severe ventricular tachyarrhythmia). Variables correlated with the occurrence of major events were history of myocardial infarction (p < 0.05) and the presence (p < 0.001) and number of segments with thallium reversible defects (p < 0.001). In multivariate analysis, history of myocardial infarction (p < 0.05) and the number of segments with reversible thallium defects (p < 0.001) were independent predictors. When all the cardiac events were taken into consideration, all the previous variables, as well as Q waves and ischemic ST abnormalities on the electrocardiogram, showed significant predictive value in both univariate and multivariate analyses. Furthermore, thallium SPECT imaging has an additive predictive value for major cardiac events over clinical and electrocardiographic risk factors. When performed on clinically selected patients at high cardiac risk undergoing abdominal aortic surgery, thallium SPECT demonstrates significant prognostic value for cardiac events over that provided by clinical variables alone.