QS Wave Research Articles

MORPHOLOGY OF INTRACORONARY THROMBI AND ITS PROGNOSIS IN YOUNG AND OLDER PATIENTS AFTER STEMI

The article presents the features of the morphologic structure of intracoronary thrombi and the prognosis of acute ST segment elevation myocardial infarction (STEMI) in patients of different age groups.
 Methods: Histological analysis of the aspirated intracoronary clots was performed in 97 patients with STEMI. The patients were divided into two groups: 11 patients aged under 44 (young group) and the remaining older than 45 (older group). The short-term prognosis was determined by: ST-segment resolution, achievement of good coronary flow, myocardial blush, indices of myocardial contractility, and QS wave formation on ECG. The study’s endpoints determined the long-term prognosis: The onset or worsening of angina symptoms, coronary revascularization (PCI or CABG), AMI, and death.
 Results: Elderly patients were substantially more likely to have a history of coronary artery disease, as well as angina attacks, or their equivalents, at rest a few days before the onset of STEMI and arterial hypertension. Dyslipidemia was significantly more common in young patients. Formation of microchannels within the thrombi was significantly more common among older patients. Achieving the target quality of microcirculation was substantially more frequent among young patients (p=0.007). The long-term prognosis was better in young patients due to the lower prevalence of the combined endpoint.
 Conclusions: Elderly patients were more likely to have intracoronary thrombi with microchannel formation, indicating a longer duration of the thrombotic process. The long-term prognosis after STEMI was significantly better in young patients.

Analytic formula for the group velocity and its derivatives with respect to elastic moduli for a general anisotropic medium

Studying the anisotropy of seismic wave velocity can provide a theoretical basis for understanding the characteristics of seismic wave propagation in anisotropic media, such as forward modeling of seismic wavefield and simultaneous inversion of anisotropic parameters. It is an important work to calculate the group velocities of three kinds of seismic waves (qP, qS1, and qS2) and the analytical expressions of the partial derivatives of the group velocities with respect to 21 elastic parameters in general anisotropic media. Therefore, a new relationship between the phase and group velocity in the general anisotropic medium is introduced first, and then the analytical expressions of the group velocity of three kinds of waves are deduced. Then, the analytical formulas of partial derivatives of the group (or phase) velocity with respect to 21 elastic parameters are derived. Finally, the distribution of partial derivatives of group slowness with respect to 21 elastic parameters with varied ray angles is analyzed and discussed. The final analytical expressions of group velocity and its partial derivatives are relatively concise and can deal with the singular points and multivalued problems of qS waves. By drawing comparison to the numerical solution of the eigenvector method, the accuracy of the analytical formula of group velocity and its partial derivatives with respect to elastic parameters are verified. The numerical simulation results indicate that the algorithm can accurately obtain the partial derivatives of group slowness with respect to 21 elastic parameters and would provide a theoretical basis for seismic ray tracing and traveltime inversion in general anisotropic media.

P3 EXERTIONAL SYNCOPE AND VENTRICULAR ARRHYTHMIA IN A PATIENT WITH CARDIAC AMYLOIDOSIS

Abstract Systemic amyloidosis is a multisystem disorder caused by the misfolding, aggregation, and deposition of certain proteins in various organs and tissues. Cardiac involvement is common and worsens the prognosis. Atrial fibrillation is the most frequent arrhythmia in cardiac amiloidosis (CA), but many cases of ventricular arrhythmias (VA) and sudden cardiac death (SCD) have been described. We present a case of a 64–year–old man admitted following exertional syncope occurred after climbing a flight of stairs. His medical history included left gonarthrosis and surgery for right carpal tunnel syndrome one year before. Physical examination did not revealed signs of heart failure. A 12–lead electrocardiogram (ECG) showed a pseudoinfarction pattern with QS waves in V2 and V3 leads and low voltage in all limb leads. Routine blood tests revealed NT–pro–BNP 3436 pg/ml(n.v.0–125) and high–sensitive troponin T 67 pg/ml(n.v.< 58). A trans–thoracic echocardiogram showed left ventricle (LV) concentric thickening wall with granular and sparkling pat[1]tern, mild reduced ejection fraction, reduced global longitudinal strain with apical sparing, grade 3 diastolic disfunction, biatrial enlargement, mild mitral regurgitation, right ventricle free wall thickening (8 mm), mild reduced TAPSE, and mild pericardial effusion. Cardiac magnetic resonance (CMR) confirmed ventricular wall thickening with evidence at T1 mapping of interstitial infiltration more evident in the septum and inferior–lateral wall with apical savings. A total body 99mTc–HDP scintigraphy showed cardiac uptake with intensity similar to bone signal (Perugini Score 2) suggesting ATTR cardiac amyloidosis. Both kappa and lambda concentrations were normal. The genetic testing did not reveled mutations in the TTR gene. We concluded for a diagnosis of ATTR wild–type CA. The Holter ECG monitoring registered numerous ventricular ectopic beats and an episode of non–sustained ventricular tachycardia. A coronary angiography ruled out coronary artery disease. In consideration of the clinical–instrumental picture an ICD was implanted. Conclusions CA is still underdiagnosed. VA and SCD may further complicate the prognosis. Early diagnosis and adequate stratification of the arrhythmic risk are essential to ensure patients the best therapeutic strategies.

P6 A HEART OF STONE: A CASE OF APOLIPOPROTEIN A–I CARDIAC AMYLOIDOSIS TREATED WITH HEART TRANSPLANT

Abstract A 56–year–old woman was referred to our Unit for advanced heart failure refractory to pharmacological therapy with poor functional status (NYHA class IV, INTERMACS profile 4–5). She had a history of restrictive and hypokinetic cardiomyopathy secondary to autosomal dominant hereditary Apolipoprotein A–I (APOA1) amylodosis caused by Leu75Pro mutation, detected both in her sister and brother. An ICD was placed for cardiac arrest due to ventricular fibrillation. She was hospitalized in our unit to evaluate non–conventional heart failure therapies. ECG showed a sinus rhythm with low QRS voltages and pseudo–infarct pattern with QS waves in V1 towards V3. Laboratory testing revealed a BNP of 625 ng/L, creatinine of 1.47 mg/dL with an estimated GFR of 40 ml/min/1.73m2. Transthoracic echocardiography showed a non–dilated left ventricle (LVEDD 50 mm, LVEDV 70 ml/m2) with concentric hypertrophy (IVS/PW 15/15 mm) and granular sparkling myocardium, global hypokinesia with severely reduced left ventricular ejection fraction (LVEF 28%) and restrictive filling. The right ventricle was dilated with reduced function (TAPSE 12 mm). Moderate mitral and tricuspid regurgitation were also reported, with estimated systolic pulmonary pressure of 40 mmHg. Right heart catheterization showed a RAP of 14 mmHg, mPAP of 31 mmHg, PCWP of 25 mmHg, PVR of 2.2 wood units and a CI of 1.49 l/min/m2; after reversibility testing with intravenous nitrate, mPAP fell to 25 mmHg, PCWP was 18 mmHg, PVR 1.86 WU and CI improved to 1.94 l/min/m2. She was dependent on inotropes (dobutamine 4 mcg/Kg/min). In multidisciplinary team, LVAD placement as a bridge was excluded for severe right ventricular dysfunction and she was listed for heart transplant in 2A emergency status. Notably, screening colonoscopy showed polypoid amyloid deposition in the bowel. Macroscopic examination of explanted heart showed thickening of both ventricles, valves and papillary muscles; histopathologic examination revealed intramural amyloid accumulation. Immunohistochemistry confirmed that amyloid deposits were specifically stained with an anti–APOA1 antibody. Postoperative course was characterized by necessity of hemodialysis, which was stopped in day 26. No amyloidosis recurrence was detected at endomyocardial biopsies up to 6 months. In selected patients with cardiac amyloidosis, heart transplantation can be an effective therapeutic option with outcomes similar to those transplanted for other causes of heart failure.

Electrocardiogram properties and risk of covert brain infarction and other magnetic resonance imaging abnormalities in a stroke-free population.

This study aimed to investigate the association between electrocardiogram (ECG) abnormalities and silent vascular brain injury as defined by cerebral magnetic resonance imaging (MRI) in a stroke-free community-based population. A total of 5888 participants were studied from the Cardiovascular Health Study (CHS), a prospective cohort of community-living older adults. Standard 12-lead ECGs measured prior to MRI scan were used. MRI scans were conducted at years 4-6 and 10-11. The primary outcome was presence of incident covert brain infarcts (CBIs) on the 2nd MRI examination, excluding previous CBIs and stroke occurrence. Secondary outcomes included white matter, ventricular, and sulcal atrophy on the 1st MRI. Logistic and multiple linear regression models were used to assess the relationship between ECG findings and silent vascular brain injury. Left axis deviation before MRI scan was related to presence of incident CBIs (odds ratio [OR]: 1.45; 95% CI: 1.01-2.08, p=.047). A long QT interval was associated with severe white matter hyperintensity (OR: 1.36; 95% CI: 1.04-1.77, p=.024). Minor Q and QS waves with ST-T abnormalities were positively related to sulcal atrophy (β: 0.43, 95% CI: 0.06-0.81, p=.023). Our study found that ECG abnormalities were related to presence of CBIs, white matter hyperintensity, and sulcal atrophy on MRI in a stroke-free relderly population. Specifically, those with left axis deviation had an increased risk of presence of CBIs.

The characteristics of a 12-lead electrocardiogram measuring premature ventricular contractions originating from the tricuspid annulus using the clock position method.

This study aimed to analyze the conventional surface electrocardiogram (ECG) characteristics of premature ventricular contractions (PVCs) originating from the tricuspid annulus and to investigate the efficacy of locating their origins according to ECG results. Eight patients who underwent radiofrequency ablation in the First Hospital of Shanxi Medical University (China) were included in the study. Pace mapping (PM) was used to analyze the characteristics of the PVCs originating from the tricuspid annulus recorded via 12-lead body surface ECGs. An R-wave was found in leads I, V5 , and V6 . The QRS wave was narrower when the PVCs originated from the septum and shifted in lead V3 (R-wave amplitude/S-wave amplitude in the precordial lead-1). The QRS wave was broadest when the PVCs originated from the 7 to 9 o'clock position. The augmented vector left lead showed RS, QS, or RSR-type waves with a low amplitude when the PVCs originated from the upper part of the annulus. When the PVCs originated from the lower part of the annulus, the augmented vector right lead reflected multidirectional and QS-type waves. The ECG-lead characteristics related to the origin of PVCs in the tricuspid annulus indicate some level of significance and can be used to formulate a specific diagnosis.

515 Exertional syncope and ventricular arrhythmia in a patient with cardiac amyloidosis

Abstract Aims Systemic amyloidosis is a multisystem disorder caused by the misfolding, aggregation, and deposition of certain proteins in various organs and tissues. Cardiac involvement is common and worsens the prognosis. Atrial fibrillation is the most frequent arrhythmia in cardiac amiloidosis (CA), but many cases of ventricular arrhythmias (VA) and sudden cardiac death (SCD) have been described. Methods and results We present a case of a 64-year-old man admitted following exertional syncope occurred after climbing a flight of stairs. In the previous 2 weeks he had experienced fatigue and poor tolerance to exertion; moreover, 2 days before he had another episode of transient loss of consciousness after exertion. His medical history included left gonarthrosis and surgery for right carpal tunnel syndrome one year before. Physical examination did not revealed signs of heart failure. A 12-lead electrocardiogram (ECG) showed a pseudoinfarction pattern with QS waves in V2 and V3 leads and low voltage in all limb leads (Figure 1). Routine blood tests revealed N-terminal pro-bran natriuretic peptide (NT-ProBNP) of 3436 pg/ml (n.v. 0–125) and high-sensitive troponin T of 67 pg/ml (n.v. < 58). A trans-thoracic echocardiogram showed left ventricle (LV) concentric thickening wall with granular and sparkling pattern, mild reduced ejection fraction, reduced global longitudinal strain with apical sparing, grade 3 diastolic disfunction, biatrial enlargement, mild mitral regurgitation, right ventricle free wall thickening (8 mm), mild reduced TAPSE, and mild pericardial effusion. Cardiac magnetic resonance (CMR) confirmed ventricular wall thickening with evidence at T1 mapping of interstitial infiltration more evident in the septum and inferior-lateral wall with apical savings (Figure 2). A total body 99mTc-HDP scintigraphy showed cardiac uptake with intensity similar to bone signal (Perugini Score 2) suggesting ATTR cardiac amyloidosis (Figure 3). Both kappa and lambda concentrations were normal. The genetic testing did not reveled mutations in the TTR gene. We concluded for a diagnosis of ATTR wild-type CA. The Holter ECG monitoring registered numerous ventricular ectopic beats and an episode of non-sustained ventricular tachycardia. A coronary angiography ruled out coronary artery disease. In consideration of the clinical-instrumental picture an ICD was implanted. Conclusions In conclusion, CA is still underdiagnosed. VA and SCD may further complicate the prognosis. Early diagnosis and adequate stratification of the arrhythmic risk are essential to ensure patients the best therapeutic strategies.

Ray velocity derivatives in anisotropic elastic media. Part II—polar anisotropy

SUMMARY Considering general anisotropic (triclinic) media and both, quasi-compressional (qP) and quasi-shear (qS) waves, in Part I of this study, we obtained the ray (group) velocity gradients and Hessians with respect to the ray locations, directions and the elastic model parameters along ray trajectories. Ray velocity derivatives for anisotropic elastic media with higher symmetries were considered particular cases of general anisotropy. In this part, Part II, we follow the computational workflow presented in Part I, formulating the ray velocity derivatives directly for polar anisotropic media (transverse isotropy with tilted axis of symmetry, TTI) for the coupled qP waves (quasi-compressional waves) and qSV waves (quasi-shear waves polarized in the ‘axial’ plane) and for SH waves (shear waves polarized in the ‘normal’ plane). The acoustic approximation for qP waves is considered a special case. In seismology, the medium properties, normally specified at regular 3-D fine gridpoints, are the five material parameters: the axial compressional and shear wave velocities, the three (unitless) Thomsen parameters and two geometric parameters: the polar angles defining the local direction (the tilt) of the medium symmetry axis. All the parameters are assumed spatially (smoothly) varying, so that their spatial gradients and Hessians can be reliably numerically computed. Two case examples are considered; the first represents compacted shale/sand rocks (with positive anellipticity) and the second, unconsolidated sand rocks with strong negative anellipticity (manifesting a qSV triplication). The ray velocity derivatives obtained in this part are first tested by comparing them with the corresponding numerical (finite difference) derivatives. Additionally, only for validation purpose, we show that exactly the same results (ray velocity derivatives) can be obtained if we transform the given polar anisotropic model parameters (five material and two geometric) into the 21 stiffness tensor components of a general anisotropic (triclinic) medium, and apply the theory derived in Part I. Since in many practical wave/ray-based applications in polar anisotropic media only the spatial derivatives of the axial compressional wave velocity are taken into account, we analyse the effect (sensitivity) of the spatial derivatives of the other parameters on the ray velocity and its derivatives (which, in turn, define the corresponding traveltime derivatives along the ray).

Pseudomyocardial Infarction: An Atypical Presentation of Chest Wall Necrotizing Fasciitis

A 75-year-old woman was admitted because of acute chest pain for one day. The electrocardiogram (ECG) showed progressive decreasing R wave amplitudes with new QS waves at precordial leads in three hours (Figure 1 A, B). Serial high-sensitivity cardiac troponin testing at baseline and three hours after admission were within normal range (8.8 pg/mL and 11.1 pg/mL respectively. Upper reference limit: 17.5 pg/mL). The white-cell count was 6800 /µL (reference range: 4800 to 10,800). The contrast-enhanced computer tomography of chest showed no aortic dissection or pulmonary embolism (Figure 3A).

СРАВНИТЕЛЬНОЕ ИЗУЧЕНИЕ ВЛИЯНИЯ ИНСУЛИНОЗАВИСИМОГО САХАРНОГО ДИАБЕТА 2-ГО ТИПА, ОТЯГОЩЕННОЙ НАСЛЕДСТВЕННОСТИ И КУРЕНИЯ НА ТЯЖЕСТЬ ИШЕМИЧЕСКОЙ БОЛЕЗНИ СЕРДЦА

Introduction. The presence of high-risk factors such as hereditary burdening, tobacco smoking, and diabetes mellitus significantly worsen the prognosis in potentially healthy individuals by increasing the incidence of coronary heart disease. Aim. To study the separate influence of insulin-dependent diabetes mellitus type 2, heredity and smoking on the severity and course of coronary heart disease. Material and methods. One hundred patients with coronary heart disease were enrolled in the study. The patients were divided according to the presence of the following high-risk factors: heredity, tobacco smoking, and insulin-dependent type 2 diabetes mellitus. The patients were examined at the beginning and 1 year after treatment. The results of echocardiography and electrocardiography were analyzed at the beginning of follow-up and one year later. The severity of coronary artery lesions was assessed using SYNTAX score analysis of coronarography protocols. The number of Q and QS waves on electrocardiogram, increased size and decreased left ventricular ejection fraction were also considered as criteria of coronary heart disease severity. The obtained data were processed using IBM Statistics SPSS-26 program. The differences were considered statistically significant at p<0,05. Results and discussion. Patients with diabetes mellitus were more susceptible to aortocoronary bypass grafting, whereas coronary angioplasty was performed more frequently in patients with heredity (p<0,05). Coronary vessels were more affected in diabetic patients and in tobacco smokers compared with patients with a burdened heredity [(20,4±2,7) points (21,9±1,39) and (12,9±1,8) points, respectively]. Severe heart failure prevailed among patients with concomitant diabetes mellitus. After one year, all patients had a reduction of clinical symptoms of angina and heart failure. The efficacy of medical treatment of angina in patients with heredity was lower compared to other groups. Conclusion. In patients with a history of diabetes mellitus development of coronary heart disease is manifested by severe myocardial and coronary lesions, which increases the risk of coronary artery bypass grafting. Despite this, patients with diabetes mellitus lend themselves well to drug treatment. The tobacco smoking group is not inferior to the diabetes mellitus group by the severity of heart and coronary artery lesions and is well amenable to drug therapy. The last place in the severity of coronary heart disease is occupied by patients with a hereditary burden, although they are more prone to acute coronary syndrome.

Response of Two-Temperature on the Energy Ratios at Elastic-Piezothermoelastic Interface

In the present investigation the reflection and transmission phenomenon of plane waves between two half spaces elastic and orthotropic piezothermoelastic with two-temperature theory is discussed. A piezothermoelastic solid half space is assumed to be loaded with an elastic half space. Due to the phenomenon, four qausi waves are obtained; quasi longitudinal (qP) wave, quasi transverse (qS) wave, quasi thermal (qT) wave and electric potential wave (eP). It is found that the amplitude ratios of various reflected and refracted waves are functions of angle of incidence, frequency of incident wave and are influenced by the piezothermoelastic properties of media. The energy ratios are computed numerically using amplitude ratios for a particular model of graphite and cadmium selenide (CdSe). The variations of energy ratios with angle of incidence are shown graphically depicting the effect of two-temperature. The conservation of energy across the interface is justified. A particular case of interest is also deduced from the present investigation.

A novel approximate formula on AVAZ of reflection and transmission qP in TTI media

This paper introduces a relational formula about crack density, crack-fill and stiffness tensor of the TI medium, and offers the relationship between anisotropic parameters and the weaknesses. We then deduce the approximate formula for the phase velocity in weakly anisotropic media on the basis of the phase velocity solved by the Christoffel equation. According to the polarization in VTI media, we establish the polarization in TTI media. Assuming that qP, SH and qS waves occur simultaneously at the anisotropic interface, simplify the 6-order Zoeppritz and deduce the explicit AVAZ formula. According to the deduced AVO formula, we analyze the anisotropic characterization of qP waves and discover that if we want to accomplish the inversion of anisotropic parameters, the incidence angle should be over 150. Also comparing the approximate curve of qP wave with the exact curve of qP wave, we discuss the effects of the azimuthal and dip angles on the approximate curve and conclude that if the azimuthal angle is around 450 or/and the dip angle is approaching 900, the error between the approximate and exact curves is becoming large. Additionally, we offer the formula of the crack parameters and the weaknesses, which indirectly shows the effects of the crack parameters on the AVAZ formula.

Novel method for the prediction of para-Hisian premature ventricular complexes from the electrocardiogram.

BackgroundCatheter ablation of para‐Hisian (PH) premature ventricular complexes (PVCs) has a high risk of heart block. This study aimed to find the electrocardiographic (ECG) predictors of PH‐PVCs.MethodsWe enrolled 47 patients who underwent an electrophysiologic study for catheter ablation of PVCs and analyzed the ECG characteristics, retrospectively.ResultsThe PVC locations were the PH in 14, right ventricular (RV) outflow tract (OT) in 11, left ventricular (LV) OT in 16, LV septum in 5, and LV summit in 1. The QRS width of the PH‐PVCs was significantly narrower than that of the rest of PVCs (140.9 ± 17.1 ms vs. 158.9 ± 19.4 ms, P = 0.004). Precordial transition of the PH‐PVCs related to sinus rhythm was not helpful in predicting the location. Lead I had monophasic R waves in 100% and lead aVR QS waves in 100%. In aVL, 13 of 14 patients had monophasic R waves, and 1 had biphasic (rS) waves with an initial positive polarity. Among the study cohort, 15 patients had a QS in aVR and R in aVL, including 13 PH‐PVCs and 2 PVCs coming from the RVOT septum and LVOT septum, respectively. The QS in aVR and monophasic R in aVL had a sensitivity of 92.8%, specificity of 93.9%, positive predictive value of 86.7%, and negative predictive value of 96.9% for localizing PH‐PVCs.ConclusionsA PVC morphology with a QS in aVR and monophasic R in aVL and QRS width <143 msec, could be used as a reliable parameter for predicting the PH location.

Usefulness of Reversed U-Curve Technique to EnhanceMapping and Ablation Efficiency in the Treatment ofPulmonary Sinus Cusp-Derived Ventricular Arrhythmias

Reversed U-curve and nonreversed U-curve (conventional technique) were both reported to be effective in treating pulmonary sinus cusp (PSC)-derived ventricular arrhythmia (VA). The aim of this study was to evaluate the characteristics between two methods. We enrolled 37 consecutive patients with PSC-derived VA who underwent radiofrequency catheter ablation using a contact force (CF)-sensing catheter. Reversed U-curve and conventional method were routinely used for each patient. For the 37 patients with PSC-VA (14 cases in left cusp [LC], 12 in right cusp, and 11 in anterior cusp), only 7 patients from the LC were ablated using conventional method whereas the others underwent successful reversed U-curve ablation. For the reversed U-curve mapping, presence of a near-field sharp potential and QS wave at the best mapping site were observed with a higher frequency; CF in 3 sinuses was always higher except for LC (p <0.001, p <0.001, and p = 0.18, respectively); the bipolar potential amplitude was significantly higher (1.52 ± 1.75 mV vs 1.02± 2.37 mV, p <0.001), and increased with CF (p <0.001). In conclusion, reversed U-curve technique allows for sufficient contact and better catheter stability, enhancing mapping and ablation efficiency in the treatment of PSC-derived VA, particularly for right and anterior sinuses.

Idiopathic Ventricular Arrhythmias Originating From the Vicinity of the Communicating Vein of Cardiac Venous Systems at the Left Ventricular Summit

The communicating vein (CV) between the great cardiac vein and small cardiac venous systems passes between the aortic and pulmonary annulus and is located in close association with the left ventricular summit (summit CV). Thirty-one patients with idiopathic ventricular arrhythmias (VAs) underwent mapping of the left ventricular summit by using a 2F microcatheter introduced into the summit CV with coronary sinus venographic guidance. Of these, 14 patients were found to have summit-CV VAs. The remaining 17 patients (control group) had VAs originating from the right ventricular outflow tract and the aortic cusps. In patients with summit-CV VAs, the earliest activation during VAs in the summit CV preceded QRS onset by 34.1±5.3 ms. The summit-CV VAs exhibited inferior axis, negative polarity in lead I, deeper QS wave in lead aVL than aVR, and nonspecific bundle branch block morphology with an R/S ratio in lead V1 of 0.67±0.33, which could be distinguishable from VAs originating from the right ventricular outflow tract and the right coronary cusp. Because of the inaccessibility of the summit CV to ablation catheter, ablation of summit-CV VAs was attempted at adjacent structures where an excellent pacemap was rarely obtained. Overall ablation success was achieved in 10 (71%) patients with summit VAs and 15 (88%) patients in control group (P=0.24). The myocardium near the summit CV can be the source of idiopathic VAs. Direct monitoring of the summit CV is helpful for identifying the site of origin and provides a landmark of the ablation target, which may facilitate ablation through adjacent structures.

Ventricular Aneurysm: Diagnosis and Treatment.

Ventricular Aneurysm: Diagnosis and Treatment.

Evaluation of Morphology of Premature Ventricular Contraction on 12-Lead Electrocardiogram

Background-Evaluation of different morphology of premature ventricular contraction (PVC) in 12-lead ECG might reflect the presence or absence of myocardial diseases and determine PVC foci. It is important for ablation procedure and it can help in pre-procedural planning and potentially may improve ablation outcome.Methods and Results-In this study, 12-lead Electrocardiogram (ECG) of 50 patients with or without structural cardiac diseases, who had experienced PVC, were obtained. PVC QRS duration, contour, pattern, unifocal or multifocaland different morphology in various lead were evaluated. PVC-QRS morphology of 50 ECGs showed QRSd d” 140ms was 60%, &gt;140ms was 24%, &gt;160ms was 16%. QRS notching &lt;40ms was 42%, &gt;40ms was 16%, smooth contour was 42%. The morphology of PVCs in lead V1, RBBB morphology was 36%, LBBB morphology was 64%; in lead V1 &amp; V2, high r 8%, low r 4%. QRS wave polarity in lead I negative (QS, Qr, or rS wave pattern) 28%, positive (R-wave pattern) 52%; in lead II, III, avF, positive 76%. Of these RR’ or Rr’ pattern 20%, R pattern 56%. Negative 24%. QRS transition in chest lead, 16% transition occur at V4 –V5, 48% at V3-V4, 4% at V2-V3, 36% at V1-V2 level. The pattern of PVCs were bigeminy 24%, trigeminy 6%, couplet 4%, salvos 12%, R on T 2%, VT 6%. Of the 32 PVCs originating from the RVOT, 8 were classified as of free-wall origin, 24 of septal, 14 of left, 26 of right, 4 of proximal, and 2 of distal origin. Of the 6 PVCs originating from the LVOT, 4 were originated from the LVOT close to the left coronary cusp and 2 were originated from the LVOT close to the right coronary cusp. Of the 12 PVCs originated from LV fascicle, 12 of posterior fascicle origin and none from anterior fascicle origin.Conclusion-12-lead ECG is a simple, inexpensive and noninvasive tool to detect PVCs and facilitate their localization. By evaluating morphology of PVC, we can also predict the structural and functional state of heart.Bangladesh Heart Journal 2016; 31(2) : 75-79

Abstract P072: Association of Occupational Exposures with Cardiovascular Disease among Hispanics/Latinos: Results from the Hispanic Community Health Study/Study of Latinos

Background: Cardiovascular disease (CVD) is a leading cause of mortality and morbidity in the US. Acute, high-dose exposures to some solvents, metals, and pesticides can be cardiotoxic, but little is known about the cardiovascular effects of chronic, low-level exposures. Thus, we evaluated cross-sectional associations of self-reported occupational exposures to solvents, metals, and pesticides with CVD prevalence among diverse Hispanics/Latinos in the US. Methods: The analyses included baseline data from 7,404 currently employed participants, ages 18-74 years, from the HCHS/SOL. CVD was defined as the presence of one or more of the following: coronary heart disease (self-reported angina, myocardial infarction, coronary bypass surgery, balloon angioplasty, or stent placement in coronary arteries, or electrocardiogram [ECG] evidence of major Q wave abnormalities or minor Q, QS waves with ST, T abnormalities); atrial fibrillation (self-reported or ECG evidence of atrial fibrillation or flutter); heart failure (self-reported); or cerebrovascular disease (self-reported stroke or transient ischemic attack). Survey-weighted Poisson regression models were used to estimate prevalence ratios (PR) and 95% confidence intervals (CIs) for each occupational exposure, adjusted for sociodemographic (age, gender, field center, Hispanic/Latino background, health insurance), acculturation (language, years of duration in the US), lifestyle (smoking, alcohol, physical activity, diet), and occupational (full- or part-time employment) characteristics. Results: Overall, 6.1% of participants had any prevalent CVD; coronary heart disease (4.3%) was most common, followed by cerebrovascular disease (1.0%), heart failure (0.8%), and atrial fibrillation (0.7%). Current occupational exposures to solvents, metals, and pesticides were reported by 6.5%, 8.5%, and 4.7% of participants, respectively. The prevalence of any CVD (PR: 2.18, 95% CI: 1.34-3.55), coronary heart disease (PR: 2.20, 95% CI: 1.31-3.71), and atrial fibrillation (PR: 5.92, 95% CI: 1.89-18.61) were significantly elevated for participants who reported current occupational pesticide exposure compared to no exposure. Current occupational metal exposure was associated with a greater prevalence of atrial fibrillation (PR: 3.78, 95% CI: 1.24-11.46). Further adjustment for hypertension, hypercholesterolemia, diabetes, or body mass index did not appreciably change the results. Current occupational solvent exposure was not associated with CVD prevalence. Conclusions: Occupational exposure to pesticides and metals is associated with higher CVD prevalence at baseline. These cross-sectional associations do not appear to be attenuated by hypertension, hypercholesterolemia, diabetes, or obesity. Further research is needed to examine other biologic mechanisms that may underlie these associations.

Infarction or Pseudo-infarction?

An applicant with a history of paroxysmal atrial fibrillation is found to have QS waves in leads III and AVF suggestive of a prior inferior wall myocardial infarction. Using the relationship between Q wave and T wave vectors in the inferior leads, an alternative explanation is explored.

An effective anisotropic poroelastic model for elastic wave propagation in finely layered media

Mesoscopic-scale heterogeneities in porous media cause attenuation and dispersion at seismic frequencies. Effective models are often used to account for this. We have developed a new effective poroelastic model for finely layered media, and we evaluated its impact focusing on the angle-dependent attenuation behavior. To enable this, an exact solution was obtained for the response of a periodically layered medium to a surface point load using Floquet’s theory. We compared this solution with that of the new model and the equivalent viscoelastic vertical transverse isotropic medium available from existing literature. We have observed that the quasi-P (qP) wave dispersion and attenuation was predicted with high accuracy by the new effective poroelastic model. For the quasi-S (qS) wave, the effective poroelastic model provides a perceptibly better prediction of the attenuation, resulting in closer to the exact waveforms. The qS-wave attenuation is underestimated by the effective viscoelastic model, whereas for the qP-wave, the model gives accurate predictions in all cases except for highly permeable weak-frame media.