Atrial septal pacing to prevent atrial fibrillation in patients with sinus node dysfunction: results of a randomized controlled study

Background

In order to assess the preventive effects of right atrial septal pacing on atrial fibrillation (AF) in patients with sinus node dysfunction, we conducted a prospective randomized controlled study in patients requiring atrial pacing.

Methods

The inclusion criterion was the presence of a sinus node dysfunction with or without episodes of AF. Pacing sites were randomized to either the right atrial septum or appendage. Patients with permanent AF or with atrioventricular (AV) block without sinus node dysfunction were excluded. Patients were discharged at a pacing rate of 65 beats per minute after setting of the optimal AV delay. The antiarrhythmic therapy remained unchanged until the first recurrence of AF. Sequential analyses were performed with the triangular test.

Results

Mean baseline characteristics were not different between the septum (n = 57) and the appendage (n = 67) groups. The triangular test evidenced a lack of effect of septal pacing at the last sequential analysis. The rates of AF-free survival were not different between the septum and the appendage group (65% vs 64%, P = .28).In the subgroup of patients with at least 1 episode of AF 3 months before pacing, AF-free survival was increased by atrial septal pacing (70% vs 40%, P = .018). The mean follow-up was 16 ± 13 months (range, 1-54).

Conclusions

Atrial septal pacing does not have a preventive effect on the occurrence of AF in patient requiring atrial pacing for sinus node dysfunction. Subgroup analysis suggests that atrial septal pacing may benefit patients with ≥1 episode of AF in the 3 months preceding pacing.     

Adaptation of the standard 12-lead electrocardiogram system dedicated to the analysis of atrial fibrillation

Objective

The objective of the study was to design a lead system aimed at studying atrial fibrillation (AF), while being anchored to the standard 12-lead system.

Methods

The location of 4 of the 6 precordial electrodes was optimized while leaving the remaining 5 of the 9 electrodes of the standard 12-lead system in place. The analysis was based on episodes of 11 different variants of AF simulated by a biophysical model of the atria positioned inside an inhomogeneous thorax. The optimization criterion used was derived from the singular value decomposition of the data matrices.

Results

While maintaining VR, VL, VF, V₁ and V₄, the 4 new electrode positions increased the ratio of the eighth and the first singular values of the data matrices of the new configuration about 5-fold compared with that of the conventional electrode positions.

Conclusion

The adapted lead system produces a more complete view on AF compared with that of the standard 12-lead system.     

Do baseline atrial electrocardiographic and infarction patterns predict new-onset atrial fibrillation after ST-elevation myocardial infarction? Insights from the Assessment of Pexelizumab in Acute Myocardial Infarction Trial

Background

Atrial infarction reportedly occurs in 0.7% to 52% of ST-elevation myocardial infarctions (STEMIs), up to two thirds of whom develop atrial fibrillation and flutter (AF). Prospective validation of electrocardiographic atrial infarction patterns is lacking. Hence, in STEMI patients treated with primary percutaneous coronary intervention, we examined whether baseline atrial electrocardiographic changes or atrial infarction patterns predicted new AF or mortality.

Methods

Within the Assessment of Pexelizumab in Acute Myocardial Infarction trial, a nested case-control study was conducted. Patients with new AF were matched 1:1 with controls, and baseline atrial electrocardiographic variables were examined.

Results

Abnormal P wave morphology (Liu minor criterion for atrial infarction) was significantly associated with new AF (adjusted odds ratio, 1.68; 1.03-2.73). This was also independently associated with 90-day mortality in the overall case-control cohort (adjusted hazard rate, 1.90; 1.04-3.46) and among patient with new-onset AF (adjusted hazard rate, 2.43; 1.22-4.84).

Conclusions

Abnormal P wave morphology significantly predicted new AF and 90-day mortality in STEMI patients.     

Linear affine transformations between 3-lead (Frank XYZ leads) vectorcardiogram and 12-lead electrocardiogram signals

Background

Recent advances in computer graphics and wireless technologies have renewed interest in vectorcardiogram (VCG) signals that use fewer leads than the conventional 12-lead electrocardiogram (ECG) signals for medical diagnostic applications. However, most cardiologists are accustomed to the 12-lead ECG even though some of the leads are either nearly aligned with or derived from the others and consequently contain redundant information. The ability to transform from orthogonal 3-lead VCG to 12-lead ECG enables the use of fewer leads for signal analysis, computer visualization, and wireless transmission of signals. This can also improve mobility, albeit limited, to the patients.

Materials and Methods

We present a statistical approach to transform 3-lead Frank VCG to 12-lead ECG signals and vice versa, based on Dower's pioneering work on lead tranformation. This approach enables compensation of baseline shifts and other constant biases present in long ECG data streams, so that the resulting statistical transforms can be more consistent and accurate. We compare the performance of the affine transform with that of Dower transform (from 3 to 12 and from 12 to 3) using the data from the PhysioNet PTB database.

Results

The results show that for both myocardial infarction (MI) and healthy control (HC) subjects, the statistical affine transform presented here maps 3-lead VCG to12-lead ECG more accurately than Dower or other lead transformation matrices of the ECG recordings.

Discussion

This investigation also shows the limitations associated with single dipole assumption that underlies Dower's geometric transformation. The results also indicate that lead transformation accuracy can be improved using separate customized transforms to, for example, age or pathologic conditions (here, MI vs HC) than a single statistical or geometric transform. Pertinently, we find that the affine transform coefficients can serve as discriminating features for classification/discrimination of MI patients from HC subjects.     

Atrial repolarization as observable during the PQ interval

Objective

We aimed to study the involvement of atrial repolarization in body surface potentials.

Methods

Electrocardiograms of healthy subjects were recorded using a 64-lead system. The data analysis focused on the PQ intervals while devoting special attention to the low-amplitude signals during the PQ segment: the segment from the end of the P wave until onset QRS. The data were analyzed by inspecting body surface potential maps and the XYZ signals of the vectorcardiogram.

Results

Standard P-wave features exhibited normal values. The local potential extremes were found at positions not sampled by the standard leads. The PQ segment was found to be not isoelectric, the time course of the potential distribution being very similar to that during the P wave but for a reversed polarity and about 3-fold lower magnitudes.

Conclusion

The results demonstrate a significant involvement of atrial repolarization during the PQ interval and essentially discordant “atrial T waves,” suggesting a small dispersion of atrial action potential durations.     

Spatial characteristics of atrial fibrillation electrocardiograms

Background

The present study investigates spatial properties of atrial fibrillation (AF) by analyzing vectorcardiogram loops synthesized from 12-lead electrocardiograms (ECGs).

Methods

After atrial signal extraction, spatial properties are characterized through analysis of successive, fixed-length signal segments and expressed in loop orientation, that is, azimuth and elevation, as well as in loop morphology, that is, planarity and planar geometry. It is hypothesized that more organized AF, expressed by a lower AF frequency, is associated with decreased variability in loop morphology. Atrial fibrillation frequency is determined using spectral analysis.

Results

Twenty-six patients with chronic AF were analyzed using 60-second ECG recordings. Loop orientation was similar when determined from either entire 60- or 1-second segments. For 1-second segments, the correlation between AF frequency and the parameters planarity and planar geometry were 0.608 (P < .001) and 0.543 (P < .005), respectively.

Conclusions

Quantification of AF organization based on AF frequency and spatial characteristics from the ECG is possible. The results suggested a relatively weak coupling between loop morphology and AF frequency when determined from the surface ECG.     

Fibrillation atriale, description de la prise en charge par les cardiologues, étude observationnelle. Résultats de l’étude Factuel

Objectives

To describe the management of patients with atrial fibrillation (AF) and to study consistency with guidelines on management of AF.

Patients and methods

Observational study on a random sample of cardiologists from a French national database. Each cardiologist had to recruit the first five patients meeting inclusion criteria (patients diagnosed with AF between January 2004 and one month before inclusion and accepting the collection of their medical data).

Results

Between December 2006 and January 2207, 1789 patients aged 71 on average have been recruited by 481 cardiologists. Fifty-one percent were diagnosed with paroxysmal, 15% with persistent and 33% with permanent AF. Restoration of sinus rhythm was preferred in forms considered as paroxysmal or persistent forms whereas control of the ventricular rate was more frequent in AF considered as permanent. Overall, therapeutic guidelines are applied in practice, despite a frequent use of amiodarone in patients with no associated heart disease. Prevention of thromboembolism was observed in 88% of the patients.

Conclusions

FACTUEL is the biggest observational study on AF ever conducted in France. The therapeutic strategies used by the cardiologists are consistent with the objectives of preventing thromboembolism and controlling heart rhythm and/or rate. In most cases, the treatment used is consistent with the therapeutic guidelines.     

Anticoagulation remains underused in prevention of stroke associated with atrial fibrillation: Insights from two consecutive national surveys

Background

Atrial fibrillation (AF) is a major risk factor of ischemic stroke. We tested whether the adoption of the CHADS₂ score in clinical guidelines has impacted treatment strategies for stroke prevention, and examined how AF affects stroke outcome.

Methods

In the setting of two national surveys [National Acute Stroke Israeli Surveys; all patients hospitalized for stroke in Israel during February-March 2004, and March-April 2007] data of patients with and without AF were analyzed with respect to patient characteristics, use of anticoagulation, stroke severity, clinical course, and long-term outcome.

Results

Of 3040 patients with acute ischemic stroke, 586 patients (19%) had a history of AF. Severe strokes on admission were significantly more frequent in patients with AF, as was the proportion of total anterior circulation strokes. Ischemic stroke associated with AF predicted poor outcome at discharge (adjusted OR 1.56; 95%CI 1.24-1.96) and higher mortality rates throughout follow-up. Among patients with a CHADS₂ score ≥ 2 prior to the index stroke and without known contraindications, 41% received anticoagulation. This proportion increased to only 62% after the index stroke, even after excluding patients with severe disability and no significant increase between 2004 and 2007 was detectable. Increasing age, in-hospital infectious complications, and unfavorable functional status at discharge were independently associated with decreased likelihood of receiving anticoagulation.

Conclusions

In deviation from current recommendations and in spite of the introduction of CHADS₂ criteria, anticoagulation for stroke prevention remains underutilized, despite the particularly poor outcome of strokes associated with AF.     

Cross-sectional epidemiology of hepatitis C virus detection and treatment in HIV-infected patients

Background

Sustained virologic response to peginterferon plus ribavirin reduces liver-related complications and mortality in patients co-infected with HIV and hepatitis C virus. Therefore, the presence of any barriers to start hepatitis C virus therapy should be identified and eliminated in order to recruit all eligible patients.

Methods

Cross-sectional study. In a HIV referral clinic we assessed the proportion of patients eligible for hepatitis C virus evaluation and treatment according to consensus guidelines.

Results

We identified 134 patients with hepatitis C virus and HIV co-infection. Twenty-one patients were excluded from the analysis due to never attending the HIV clinic (n = 12) or having hepatitis C virus RNA not detectable (n = 9). In the remaining 113 patients, only 61% had identification of hepatitis C virus genotype and quantification of hepatitis C viral load. Thirty-six patients started peginterferon plus ribavirin, and 16 (44%) achieved sustained virologic response. Seventy-seven patients did not receive treatment for hepatitis C virus due to the presence of medical contraindications (n = 22), provider barriers (n = 15), or patient barriers (n = 40). Multivariate analysis identified lower education degree (odds ratio: 4.53; 95% confidence intervals: 1.36-15.16, p = 0.014) and patient civil status single, separated or widower (odds ratio: 4.81; 95% confidence intervals: 1.54-14.99, p = 0.007) as the independent determinants associated to not initiating therapy for hepatitis C virus infection in patients with barriers.

Conclusion

A minor proportion of HIV-infected patients received appropriate assessment and treatment for hepatitis C virus infection. Social disadvantages require multidisciplinary models of health care to improve hepatitis C virus treatment initiation and success.     

Genetic variation and activity of the renin-angiotensin system and severe hypoglycemia in type 1 diabetes

Background

The deletion-allele of the angiotensin-converting enzyme (ACE) gene and elevated ACE activity are associated with increased risk of severe hypoglycemia in type 1 diabetes. We explored whether genetic and phenotypic variations in other components of the renin-angiotensin system are similarly associated.

Methods

Episodes of severe hypoglycemia were recorded in 171 consecutive type 1 diabetic outpatients during a 1-year follow-up. Participants were characterized at baseline by gene polymorphisms in angiotensinogen, ACE, angiotensin-II receptor types 1 (AT1R) and 2 (AT2R), and by plasma angiotensinogen concentration and serum ACE activity.

Results

Three risk factors for severe hypoglycemia were identified: plasma angiotensinogen concentration in the upper quartile (relative rate [RR] vs. lower quartile 3.1, 95% confidence interval [CI,] 1.4-6.8), serum ACE activity in the upper quartile (RR vs. lower quartile 2.9, 95% CI, 1.3-6.2), and homo- or hemizygosity for the A-allele of the X chromosome-located AT2R 1675G/A polymorphism (RR vs. noncarriers 2.5, 95% CI, 1.4-5.0). The three risk factors contributed independently to prediction of severe hypoglycemia. A backward multiple regression analysis identified a high number of renin-angiotensin system-related risk factors and reduced ability to perceive hypoglycemic warning symptoms (impaired hypoglycemia awareness) as predictors of severe hypoglycemia.

Conclusions

High renin-angiotensin system activity and the A-allele of the AT2R 1675G/A polymorphism associate with high risk of severe hypoglycemia in type 1 diabetes. A potential preventive effect of renin-angiotensin system blocking drugs in patients with recurrent severe hypoglycemia merits further investigation.     

Association of rate-controlled persistent atrial fibrillation with clinical outcome and ventricular remodelling in recipients of cardiac resynchronization therapy

Background

Whether patients with persistent atrial fibrillation (AF) obtain the same degree of benefit with cardiac resynchronization therapy (CRT) as those in sinus rhythm remains unclear.

Methods

We enrolled 93 patients undergoing CRT implantation, 20 (22%) of whom had rate-controlled persistent AF. The primary endpoint was CRT response defined as 1 class improvement in Specific Activity Scale and 15% reduction in left ventricular end-systolic volume (LVESV) during 12 months. Other endpoints included changes in 6-minute walk distance, quality of life, B-type natriuretic peptide, and survival.

Results

Baseline characteristics were similar in those with and without AF. Response to CRT was observed in 42% vs 54% of those with and without AF, respectively (P = 0.3). Both groups had significant improvements in 6-minute walk distance, quality of life, and LVESV, but the improvement in LVESV was smaller in those with AF (13.7% ± 14.9% vs 27.7% ± 23.7%; P = 0.02). During 2.8 ± 1.4 years of follow-up, AF was associated with a 2.2-fold increased risk of death or transplantation (95% confidence interval, 1.2-3.9; P = 0.01).

Conclusions

Compared with patients without rate-controlled persistent AF, those with rate-controlled persistent AF had similar rates of clinical improvement but less left ventricular reverse remodelling in the first year after CRT. AF was associated with a markedly higher risk of death or transplantation in long-term follow-up. Given these findings, randomized studies assessing CRT efficacy in those with AF are warranted.     

Influence of structural heart disease on characteristics of atrial fibrillation recurrence in patients with dual-chamber pacemakers

Aims

The aim of the study was to prospectively examine the influence of structural heart disease (SHD) and sinus node dysfunction (SND) on the frequency and duration of atrial fibrillation (AF) episodes in patients with implanted pacemakers.

Methods

We examined episodes of AF in 207 patients (93 with SHD; 165 with SND) with known or suspected paroxysmal AF who underwent dual-chamber pacing.

Results

Seventy-one percent of all patients experienced at least one episode of AF during follow-up, with a mean burden of 3.3 ± 6.4 h/d (median, 0.2 hours) and a mean frequency of 11.7 ± 26.0 episodes per day (median, 1.4). The proportion of episodes longer than 6 hours was greater in patients with SHD when compared to patients without SHD. In a logistic regression model adjusted for SND, gender, and the 2-way interactions of SND, sex, and SHD, SHD was a significant factor (P = .0188) with the odds ratio of having an episode longer than 6 hours 3.4 times higher for patients with SHD than for patients without SHD. Older patients with SHD had less frequent but longer episodes compared to younger patients. In patients without SHD, there was no comparable age difference. Burden, frequency, and average episode length were not influenced by the presence or absence of SND.

Conclusions

Patients with SHD have longer episodes of AF supporting the concept that SHD influences the underlying substrate to favor perpetuation.     

Mirror image electrocardiograms and additional electrocardiographic leads: new wine in old wineskins?

Background

Mirror image electrocardiograms (ECGs), obtained by inverting the original signals, and additional precordial leads have been proposed as means to improve ECG diagnosis. The theoretical backgrounds of these proposals are discussed.

Methods

In 746 body surface potential maps, the mirror areas of the 6 precordial leads, V₃R, and 2 more leads higher up and 1 lower down the thorax have been determined. The similarity between the original signal and its mirror image was expressed by a similarity index. This was done separately for QRS and ST-T; for the first and second parts of QRS; and for the categories normal, left ventricular hypertrophy, and infarct.

Results

In general, high similarity scores were obtained. The mirror images of V₁ and V₂ are almost diametrically located on the back. Inverting these leads could render the V₈ and V₉ leads. The other mirror areas may deviate considerably from where generally expected.

Conclusion

Mirror images can be obtained consistently from all locations, supporting the dipole representation of cardiac electrical activity. Neither mirror image ECGs nor additional chest leads contribute essentially to ECG diagnosis.     

Angiotensin-converting enzyme inhibitors as adjunctive therapy in patients with persistent atrial fibrillation

Objectives

The purpose of the current study was to assess the effect of angiotensin-converting enzyme inhibitor (ACEI) therapy in facilitating cardioversion from persistent atrial fibrillation (AF) and maintaining sinus rhythm.

Background

Pharmacologic therapy and electrical cardioversion for AF are often unsuccessful in maintaining long-term sinus rhythm.

Methods

The current study, a 1-year, prospective follow-up, comprised 47 patients with persistent AF undergoing electrical cardioversion. Patients receiving ACEI were compared with those receiving other medications. The study end point was the number of defibrillation attempts required for atrial defibrillation and the number of hospital admissions. A secondary end point was change in signal-averaged P-wave duration (SAPD) 1 year after successful electrical cardioversion.

Results

Of those admitted and requiring electrical defibrillation, the number of defibrillation attempts required for successful cardioversion was significantly less in the ACEI group (P < .001). The incidence rate ratio for admissions comparing recipients of ACEI with others was 0.14 (P = .03). Patients receiving ACEI therapy had significantly lower SAPD at 1 year when compared with the no-ACEI group (135 ms ± 3 vs 150 ms ± 2, P = .002).

Conclusions

The use of long-term ACEI therapy facilitated electrical defibrillation in patients with persistent AF. ACEI therapy also reduced SAPD, suggesting amelioration of the arrhythmogenic substrate. Furthermore, we confirmed that SAPD is prolonged in patients with persistent AF.     

Does modifying electrode placement of the 12 lead ECG matter in healthy subjects?

Background

Limb electrodes for the 12 lead ECG are routinely placed on the torso during exercise stress testing or when limbs are clinically inaccessible. It is unclear whether such electrode modification produces ECG changes in healthy male or female subjects that are clinically important according to the 2009 AHA, ACCF, HRS guidelines. We therefore measured whether ECG modification produced clinically important or false positive ECG changes e.g., appearance of Q waves in leads V_1-3, ST changes greater than 0.1 mV, T wave changes greater than 0.5 mV (frontal plane) or 1 mV (transverse plane), QRS axis shifts or alterations to QTc/P-R/QRS intervals.

Methods

The 12 lead ECG was measured in 18 healthy and semi-recumbent subjects using the standard and Takuma modified limb placements.

Results

In the frontal plane we demonstrate that the modification of limb electrode placement produces small Q, R and T wave amplitude and QRS axis changes that are statistically but not clinically significant. In the transverse plane it produces no statistically or clinically significant changes in the ECG or in ST segment morphology, P-R, QRS or QTc intervals.

Conclusions

We provide better and more robust evidence that routine modification of limb electrode placement produces only minor changes to the ECG waveform in healthy subjects. These are not clinically significant according to the 2009 guidelines and thus have no effect on the clinical specificity of the 12 lead ECG.     

When deriving the spatial QRS-T angle from the 12-lead electrocardiogram, which transform is more Frank: regression or inverse Dower?

Introduction

Our primary objective was to ascertain which commonly used 12-to-Frank-lead transformation yields spatial QRS-T angle values closest to those obtained from simultaneously collected true Frank-lead recordings.

Materials and Methods

Simultaneous 12-lead and Frank XYZ-lead recordings were analyzed for 100 postmyocardial infarction patients and 50 controls. Relative agreement, with true Frank-lead results, of 12-to-Frank-lead-transformed results for the spatial QRS-T angle using Kors' regression versus inverse Dower was assessed via analysis of variance, Lin's concordance, and Bland-Altman plots.

Results

Spatial QRS-T angles from the true Frank leads were not significantly different than those derived from the Kors' regression-related transformation but were significantly smaller than those derived from the inverse Dower-related transformation (P < .001). Independent of method, spatial mean QRS-T angles were also always significantly larger than spatial “maximum” (“peaks”) QRS-T angles.

Discussion

Spatial QRS-T angles are best approximated by regression-related transforms. Spatial mean and spatial “peaks” QRS-T angles should not be used interchangeably.     

Atrial Fibrillation: A Real-Life Observational Study in the Québec Population

Background

Atrial fibrillation (AF) is the most common cardiac arrhythmia and has been associated with heart failure, stroke, and mortality. The prevalence of AF is expected to rise with the aging population. Our objectives were to characterize the Québec AF patient population at the time of diagnosis of AF, quantify medical resource use prior to and after the initial diagnosis of AF, and determine overall survival.

Methods

A retrospective cohort study was undertaken using the Régie de l'Assurance Maladie du Québec databases to evaluate patients diagnosed with AF between January 1, 1998, and April 30, 2009.

Results

A total of 64,157 patients were included in our study population. At the time of diagnosis of AF, patients also suffered from several diseases, including heart failure (15.8%) and angina pectoris (15.1%). Compared with the year prior to AF diagnosis, in the year after AF diagnosis patients were more frequently hospitalized (1.5 vs 1.1 hospitalizations) and for longer periods (5.6 vs 3.3 days), and had more outpatient visits (12.9 vs 11.7). Survival rapidly decreased during the first 60 days (60-day mortality, 6.1%) and steadily declined thereafter, with mortality rates of 14.7% and 36.8% at 1 and 5 years, respectively.

Conclusion

At the time of diagnosis of AF, patients often suffer from several comorbidities. Diagnosis of AF is associated with an increase in medical resource use and higher mortality rates, particularly within the first 60 days.     

Similarity of ST and T waveforms of 12-lead electrocardiogram acquired from different monitoring electrode positions

Background

It is not always feasible to use standard electrode placement for limb leads when recording the 12-lead electrocardiogram (ECG). Other electrode placements have been accepted during monitoring. Nonstandard electrode positions, however, fail to produce waveforms identical to those recorded from the distal limb positions that are standard for diagnostic interpretation. The purpose of the present study was to validate the ST-T-segment for an alternative “Lund system” of proximal limb electrode sites.

Methods

Twelve-lead ECGs (standard, Mason-Likar, and Lund lead placement) were collected from 167 patients.

Results

There were systematic differences between measurements from standard vs Mason-Likar, but not vs the Lund system. The 95% confidence intervals of measurement agreement were similar or less when comparing measurements from the Lund system vs the first standard recording with measurements for the 2 standard recordings.

Conclusion

The Lund system might constitute a uniform convention for “diagnostic” ECGs as well as for monitoring ECG applications with regard to ST-T waveforms.     

New precordial bipolar electrocardiographic leads for detecting left ventricular hypertrophy

Background

Novel small and wearable electrocardiogram (ECG) devices offer new means of recording cardiac activity in different applications. Our objective was to evaluate the performance of closely separated (6 cm) bipolar leads in differentiating subjects with left ventricular hypertrophy (LVH) from healthy subjects.

Methods

The material contained body surface ECG of 236 healthy and 116 LVH subjects. A total of 36 vertical, 30 horizontal, and 66 diagonal bipolar leads located on the anterior thorax were analyzed. The QRS amplitudes were calculated, and the leads' overall diagnostic performance was assessed by receiver operating characteristic (ROC) analysis.

Results

The best overall diagnostic performances were obtained from 2 areas: one near the precordial electrodes of standard leads V₁ to V₃ and the other on lower anterior thorax. Vertical and diagonal bipolar leads located at lower anterior thorax provided the highest ROC areas (≥0.79). These bipolar leads also provided similar sensitivities than the traditional Sokolow-Lyon method.

Conclusion

The new short distance vertical and diagonal bipolar leads are efficient in discriminating subjects with LVH from healthy subjects based on QRS amplitude.     

Electrocardiographic differentiation between occlusion of the first diagonal branch and occlusion of the left anterior descending coronary artery

Purpose

We sought to electrocardiographically distinguish ST-segment elevation (STE)-acute myocardial infarction (AMI) caused by occlusion of the first diagonal branch (D1) from STE-AMI caused by occlusion of the left anterior descending coronary artery (LAD).

Methods

We examined 28 patients with STE-AMI caused by D1 occlusion (G-D) and 342 with STE-AMI caused by LAD occlusion (G-L).

Results

G-D had a higher prevalence of STE ≥0.5 mm in each of leads I and aVL and a lower prevalence of STE ≥1 mm in each of leads V₁ through V₆ than G-L. The prevalence of STE ≥0.5 mm in lead aVL without STE ≥1 mm in lead V₁ was higher in G-D (82.1%) than in G-L (9.4%, P < .01).

Conclusion

ST-segment elevation ≥0.5 mm in lead aVL without STE ≥1 mm in lead V₁ may be useful to distinguish STE-AMI caused by occlusion of the D1 from STE-AMI caused by occlusion of the LAD.