Left Anterior Descending Artery Territory Research Articles

Ventricular tachycardia ablation after myocardial infarction guided by cardiac magnetic resonance/multidetector computed tomography image integration

Abstract INTRODUCTION The persistent challenge of ventricular tachycardia (VT) ablation lies in the elevated morbidity and mortality due to the underlying disease progression and the complexity of the arrhythmogenic substrate. As imaging methods are evolving, substrate-based VT ablation is moving closer to the realm of precision medicine. CASE PRESENTATION A 52-year-old patient with a history of hypertension, type II diabetes mellitus, hyperlipidemia, and stage IIIB chronic kidney disease was referred to our hospital for sustained monomorphic VT. Upon admission, the patient was hemodynamically stable. Laboratory results indicated mild anemia, moderate renal dysfunction, and normal myocardial enzymes. ECG during sinus rhythm showed widespread repolarization abnormalities in the apical and postero-lateral leads. Echocardiography revealed mild left ventricular dysfunction and coronary angiography confirmed significant lesions in multiple coronary arteries that were treated with drug-eluting stents (DES). Cardiac MRI showed relatively limited areas of old myocardial infarctions in the left circumflex artery and left anterior descending artery territories, therefore we decided to perform VT ablation. We used a Carto 3 Biosense Webster electro-anatomical mapping system (EAM) guided by fusion imaging (cardiac MRI and multidetector computed tomography - MDCT) with the aid of ADAS 3D software. The voltage map created during sinus rhythm, was concordant with the lesions identified on LGE-CMR. Radiofrequency (RF) catheter ablation targeted abnormal signals from the EAM, which were identified based on conduction channels (CCs) from the fusion imaging. There was complete VT non-inducibility at programmed ventricular stimulation (PVS). At the 3-month follow-up, echocardiography showed a slight improvement in LVEF and repeated PVS proved persistent ventricular arrhythmia non-inducibility. CONCLUSION Substrate-based VT ablation in structural heart disease has greatly improved by high-resolution substrate imaging with detailed anatomy, allowing successful personalized treatment. There is room for further improvement in the near future with the contribution of artificial intelligence, possibly with a more targeted and automated VT ablation.

Do False Tendons Prevent Adverse Left Ventricular Remodeling After Anterior Wall Myocardial Infarction? An Echocardiographic Strain Imaging Study

The role of muscular left ventricular (LV) false tendons (FTs) is poorly understood. To gain insight into their pathophysiologic significance, we adapted echocardiographic LV strain imaging software to measure LVFT longitudinal strain in subjects with normal left ventricles and in patients who sustained previous anterior wall myocardial infarction (AWMI). GE EchoPAC software was used to measure longitudinal strain in LVFTs ≥0.3 cm in diameter. Tendinous strain was measured in 11 patients with LVFTs confined to the left anterior descending artery territory (connecting the anteroseptum or anterior wall to the apex) ≥6 months after AWMI (myocardial infarction [MI]+FT+ group) and in 25 patients with normal hearts containing LVFTs (MI-FT+ group). We also compared the indexed LV end-diastolic volumes in the MI+FT+ group to that of 25 patients with previous AWMI without LVFTs (MI+FT- group). The mean LVFT strain in MI+FT+ group was 5.5 ± 6.2% and -28.9 ± 4.7% in the MI-FT+ group (p <0.0001). The indexed LV end-diastolic volume in the MI+FT+ group did not differ from the MI+FT- group (88.4 ± 17.8 vs 87.9 ± 17 ml/m2, p = 0.90). In conclusion, the negative strain (contraction) developed by LVFTs in the MI-FT+ group may help maintain normal LV size and shape by generating inward restraining forces. The development of positive strain (stretch) in LVFTs in patients in the MI+FT+ group suggests they become infarcted after AWMI. This implies that they are incapable of generating inward restraining forces that might otherwise mitigate adverse remodeling. Of note, LV volumes after AWMI do not differ whether or not LVFTs are present.

Ventricular arrhythmia inducibility in porcine infarct model after stereotactic body radiation therapy

BackgroundVentricular arrhythmia (VA) is the primary mechanism of sudden death in patients with structural heart disease. Cardiac stereotactic body radiation therapy (SBRT) delivered to the scar in the left ventricle significantly reduces the burden of VA. ObjectiveThe goal of this study was to investigate the impact of SBRT on scar morphology and VA inducibility in a porcine infarct model. MethodsMyocardial infarction (MI) was created in 10 Yorkshire pigs involving the left anterior descending artery territory. Cardiac positron emission tomography and computed tomography were performed for targeted SBRT. Alternative pigs received SBRT at 25 Gy in a single fraction. The terminal experiment included endocardial mapping, programmed ventricular stimulation, and tissue harvesting. ResultsOf the 10 pigs infarcted, 2 died prematurely after MI and 8 (4 MI and 4 MI+SBRT) survived. Mean time from MI to SBRT was 48 ± 12 days, and mean time from SBRT to harvest was 32 ± 12 days. Scar was localized on intracardiac mapping in all pigs, and the scar was denser in the MI+SBRT compared with the MI-only group (33% ± 20% vs 14% ± 11%; P = .07). All 4 MI pigs had inducible VA during programmed stimulation, whereas only 1 of 4 pigs had inducible VA in the MI+SBRT arm (100% vs 25%; P = .07). No myocardial fibrosis was seen in the remote areas in either group. ConclusionSBRT reduced VA inducibility in pigs with scarring after MI. Endocardial mapping revealed denser scar in pigs receiving SBRT compared with those that did not, suggesting that SBRT suppresses VA inducibility through better scar homogenization.

Characteristics and Outcomes of Young Patients With ST-Elevation Myocardial Infarction Without Standard Modifiable Risk Factors

Patients with ST-elevation myocardial infarction (STEMI) with no standard modifiable risk factors (SMuRFs: hypertension, diabetes mellitus, hypercholesterolemia, and smoking) have worse short-term mortality than those with SMuRFs. Whether this association extends to younger patients is unclear. A retrospective cohort study was performed of patients aged 18 to 45 years with STEMI at 3 Australian hospitals between 2010 and 2020. Nonatherosclerotic causes of STEMI were excluded. The primary outcome was 30-day all-cause mortality. Secondary outcomes included 1 and 2-year mortality. Cox proportional hazards analysis was used. Of 597 patients, the median age was 42 (interquartile range 38 to 44) years, 85.1% were men and 8.4% were SMuRF-less. Patients who are SMuRF-less were >2 times more likely to have cardiac arrest (28.0% vs 12.6%, p=0.003); require vasopressors (16.0% vs 6.8%, p=0.018), mechanical support (10.0% vs 2.3%, p=0.046), or intensive care admission (20.0% vs 5.7%, p <0.001); and have higher rate of left anterior descending artery infarcts than those with SMuRFs (62.0% vs 47.2%, p=0.045). No significant differences in thrombolysis or percutaneous intervention were observed. Guideline-directed medical therapy at discharge was high (>90%), and not different in the SMuRF-less. 30-day mortality was almost fivefold higher in the SMuRF-less (hazard ratio 4.70, 95% confidence interval 1.66 to 13.35, p=0.004), remaining significant at 1 and 2 years. In conclusion, young patients who are SMuRF-less have a higher 30-day mortality after STEMI than their counterparts with SMuRFs. This may be partially mediated by higher rates of cardiac arrest and left anterior descending artery territory events. These findings further highlight the need for improved prevention and management of SMuRF-less STEMI.

Chronic ischemia in Left anterior descending artery territory presenting as intractable hiccups: An unusual symptom of coronary artery disease.

Classical symptoms of ischemic heart disease include exertional chest pain associated diaphoresis, palpitations or shortness of breath. Yet, it can also present unusually with symptoms ranging from epigastric discomfort, fatigue and vomiting. A 48 years old male presented to the hospital with severe retrosternal chest pain for 6 hours duration. ECG showed acute anterior wall STEMI. Primary PCI to LAD was performed successfully. He had been complaining of intractable hiccups for the past one year for which he had been seen in gastroenterology clinics multiple times with no relief in hiccups. After we performed primary PCI to LAD, he had complete resolution of hiccups. He is still under regular follow up with us for the past 4 months with no active complaints of hiccups. This case conclude that Intractable hiccups can be the only symptomatic manifestation of coronary artery disease (CAD) in some patients. Therefore, a high suspicion of CAD should be kept in mind especially in patients with risk factors for CAD.&#x0D;

Ventricular arrhythmias following coronary artery bypass grafting for ischemic cardiomyopathy: When to insert an implanted cardioverter defibrillator?

ObjectivesThe study objectives were to determine the incidence, predictors, and clinical impact of ventricular arrhythmias after coronary artery bypass grafting and to evaluate the impact of implantable cardioverter defibrillators on the survival of patients with ventricular arrhythmias. MethodsWe enrolled 498 patients with a left ventricular ejection fraction of 40% or less who underwent coronary artery bypass grafting between 1993 and 2015. Clinical follow-up was completed in 94.0% of patients, with a median follow-up of 58.4 months. ResultsOverall, 212 patients (43%) died, mainly of heart failure (n = 54, 10.8%) or sudden cardiac death (n = 40, 8.0%). The sudden cardiac death rate was highest during the first 6 months, with a monthly rate of 0.37%. Overall, 99 patients (20%) developed postoperative ventricular arrhythmias, and implantable cardioverter defibrillator was implanted in 55 patients. Previous ventricular arrhythmias (hazard ratio, 3.22; 95% confidence interval, 1.98-5.24; P < .001), left ventricular end-systolic dimension (hazard ratio, 1.07; 95% confidence interval, 1.04-1.10; P < .001), and myocardial infarction in the left anterior descending artery territory (hazard ratio, 1.73; 95% confidence interval, 1.10-2.73; P = .02) were independent predictors of postoperative ventricular arrhythmias. Notably, the 5-year survival of patients with ventricular arrhythmias who received an implantable cardioverter defibrillator was significantly higher than that of patients with ventricular arrhythmias who did not receive it (76.1% vs 22.7%, P < .001) and was comparable to that of patients without ventricular arrhythmias (76.1% vs 73.6%, P = .98). ConclusionsSudden cardiac death affects a significant proportion of patients with ischemic cardiomyopathy undergoing coronary artery bypass grafting, most frequently within 6 months postoperatively. To prevent sudden cardiac death, earlier implantable cardioverter defibrillator implantation should be indicated for high-risk patients with scars in the left anterior descending artery territory and excessive left ventricular remodeling.

P157 THE UNFORESEEABLE LINK: A CASE OF CORONARY–PULMONARY ARTERY FISTULA BRIDGING THE RIGHT CORONARY AND FIRST SEPTAL BRANCH OF THE LEFT ANTERIOR DESCENDING ARTERY

Abstract Coronary–pulmonary artery fistulas are a rare clinical entity with a variety of potential clinical manifestations. Albeit rare, such anomalies may in some instances involve multiple coronary arteries and go unnoticed until old age producing little to no clinical manifestations. We hereby present the case of an 83–year–old man, heavy smoker, with a history of cor pulmonale due to severe chronic obstructive pulmonary disease (COPD) who was recently diagnosed with metastatic lung adenocarcinoma. Incidentally, one of the ECGs performed revealed negative T waves in the precordial leads in the absence of symptoms and with a negative troponin curve. Echocardiography was thus performed and revealed severe left ventricular systolic dysfunction (EF 31%) with infero–postero–lateral akinesia. The patient underwent CT coronary angiogram, which ruled out any significant coronary stenosis but revealed a most surprising finding. An ectatic arterial branch running anteriorly and draining into the pulmonary artery connected the the proximal segment of the right coronary artery to the first septal branch of the left anterior descending (LAD) artery. Unfortunately, the severe left ventricular failure contraindicated any chemotherapy and the patient was discharged with a plan to start palliative radiotherapy. Three months later, the patient returned to our Hospital due to worsening weakness, cachexia and one episode of pre–sincope. During this hospital stay, he developed atypical chest pain with a significant troponin curve. A HRCT and pulmonary angiogram was performed, which revealed neoplastic progression with bilateral lung involvement and bone metastases, as well as bilateral segmental pulmonary emboli. Echocardiography demonstrated new segmental areas of akinesia (apical septum and mid–apical anteroseptal segment) suggestive of focal ischemic damage. Given the documented pulmonary embolism and the anomalous connection between pulmonary artery and coronary circulation, this event may have been caused by paradoxical embolism travelling from pulmonary to coronary circulation (most likely affecting the LAD artery territory). Due to the patient’s frailty however, this hypothesis could not be confirmed by coronary angiography. Despite their relative rarity, coronary–pulmonary artery fistulas involving multiple coronary arteries can occur in the elderly population with no previous clinical manifestations and may give rise to apparently unfathomable clinical constellations.

Coronary vasomotor dysfunction in cancer survivors treated with thoracic irradiation

BackgroundWe sought to test the hypothesis that thoracic radiation therapy (RT) is associated with impaired myocardial flow reserve (MFR), a measure of coronary vasomotor dysfunction. MethodsWe retrospectively studied thirty-five consecutive patients (71% female, mean ± standard deviation (SD) age: 66 ± 11 years) referred clinically for positron emission tomography/computed tomography (PET/CT) myocardial perfusion imaging at a median (interquartile range, IQR) interval of 4.3 (2.1, 9.7) years following RT for a variety of malignancies. Radiation dose-volume histograms were generated for the heart and coronary arteries for each patient. ResultsThe median (IQR) of mean cardiac radiation doses was 12.0 (1.2, 24.2) Gray. There were significant inverse correlations between mean radiation dose and global MFR (MFRGlobal) and MFR in the left anterior descending artery territory (MFRLAD): Pearson’s correlation coefficient = − .37 (P = .03) and − .38 (P = .03), respectively. For every one Gray increase in mean cardiac radiation dose, there was a mean ± standard error decrease of .02 ± .01 in MFRGlobal (P = .04) and MFRLAD (P = .03) after adjustment. ConclusionsIn patients with a history of RT clinically referred for cardiac stress PET, we found an inverse correlation between mean cardiac radiation dose and coronary vasomotor function.

A historical appraisal of the techniques of left ventricular volume reduction in ischemic cardiomyopathy: Who did what?

Resection or exclusion of scars following a myocardial infarction on the left anterior descending artery territory started even before the beginning of the modern era of cardiac surgery. Many techniques were developed, but there is still confusion on who did what. The original techniques underwent modifications that brought to a variety of apparently new procedures that, however, were only a "revisitation" of what described before. In some case, old techniques were reproposed and renamed, without giving credit to the surgeon that was the original designer. Herein we try to describe which are the seminal procedures and some of the most important modifications, respecting however the merit of who first communicated the procedure to the scientific world.

Can the 12-Lead Electrocardiogram Predict Myocardial Viability?

Introduction: In patients with coronary artery disease and left ventricular dysfunction, the assessment of myocardial viability, prior to revascularisation has been shown to be of significant benefit. Most methods to assess myocardial viability such as Positron Emission Tomography (PET) and Cardiac MRI (CMR) are not readily available in resource constrained settings. The present study sought to determine if an easily available and inexpensive tool, such as the 12-lead surface Electrocardiogram (ECG) can be used as a screening tool to assess for myocardial viability. It is hypothesised that the R wave height as a marker of electrical activity would correlate with viability. Aim: To determine if the surface ECG can be used to predict myocardial viability. Materials and Methods: This retrospective study was conducted at the Christian Medical College and Hospital, Vellore, Tamil Nadu, India. Among all patients who had undergone CMR viability assessment as part of their routine care between February 2008 and October 2017, and analysis and preliminary write up was done between November 2017 and Decemeber 2018, 119 patients with previous anterior wall myocardial infarctions were identified. The 12-Lead ECGs of these patients were assessed for the height of R wave in lead V3 and sum of R wave heights in all precordial leads. Myocardial viability was assessed based on the extent of Late Gadolinium Enhancement (LGE) on CMR. Measures of diagnostic accuracy including sensitivity, specificity, predictive values and likelihood ratios were calculated. Results: It was found that a R wave height of less than 3 mm in lead V3 was 90.3% sensitive for the detection of non viable myocardium. Similarly, when the sum of the R wave heights in all precordial leads was less than 28.5 mm, it was 93.2% sensitive for the detection of non viable myocardium. Conclusion: In patients with previous anterior wall myocardial infarctions when the R wave height was less than 3 mm in lead V3, it was 90.3 % sensitive to identify those with non viable Left Anterior Descending artery (LAD) territory. The 12-Lead ECG is therefore a sensitive, inexpensive and easily available screening test to assess for LAD territory non viability.

P1309 A jellyfish in the sea

Abstract Background The unexpected presence of a left ventricular (LV) mass is always a cause of concern for physicians. This is especially so in the presence of a cerebrovascular accident and a recent cardiac event, where the hunt for a cardioembolic source begins. We describe a case of an unusual presentation of a LV thrombus masquerading as a cystic mass, where diagnosis was confirmed with multimodality imaging tools. Purpose A 58 year old Thai male first presented to the emergency department with left brachio-facial syndrome secondary to a right pre-central gyrus stroke. He had chest pain 2 days prior, and was pain free on admission. An electrocardiogram done showed an evolved anterior myocardial infarction. Methods and Results A transthoracic echocardiogram performed on the 4th day of admission revealed a mildly impaired left ventricular systolic function with an ejection fraction of 45%, and wall motion abnormalities in the left anterior descending artery territory. There was an apical gelatinous-like, cystic and mobile mass with soft flexible walls, measuring 2.4 X 2.1cm. Differentials at this point included cystic thrombus, hydatid cyst, capillary haemangioma and intracardiac tumour. A cardiac MRI was performed which showed an irregular apical mass with features suggestive of fresh thrombus. The mass demonstrates hyperintensity T1-w FSE sequences (with and without fat sat), increased hyperintensity in T2-w triple IR FSE, with no increased uptake in first pass perfusion, T1-w post contrast, or early and late gadolinium enhancement images. A repeat transthoracic echocardiogram done 11 days after anticoagulation showed a 50% reduction in the size of the mass. See images below for more information. Conclusion In the era of early primary percutaneous coronary intervention and anticoagulation following an acute myocardial infarction (AMI), LV thrombus is an uncommon complication. It can occur within 2 weeks after an AMI, where increased blood stasis from dyskinesia or akinesia of associated wall segments, and a hypercoagulable state increases the risk of thrombus formation. A literature search has shown that presentation of the thrombus as a cystic mass is rare as well. As such, early diagnosis allowing for early treatment, especially when systemic embolism of thrombus is suspected, is important. Other causes of cystic LV thrombus do need to be considered in the relevant clinical context. These include infectious causes such as hydatid cyst, capillary hemangioma or intracardiac tumour, which are less likely given the history and investigation results. In this case, a trial of therapy with anticoagulation reduced the size of the cystic mass, and along with imaging findings, confirmed the diagnosis of a cystic LV thrombus. Abstract P1309 Figure. TTE and MRI heart

Type 9 Dual Left Anterior Descending Artery or Triple Left Anterior Descending Artery Anomaly: A Rare Anomaly

A middle aged patient presented with acute coronary syndrome. Echocardiography showed regional wall abnormality in the left anterior descending artery territory with reduced left ventricular dysfunction. Coronary angiogram showed early division, suggestive of a rare case of dual LAD.

Usefulness of Myocardial Longitudinal Strain in Prediction of Heart Failure in Patients with Successfully Reperfused Anterior Wall ST-segment Elevation Myocardial Infarction.

Background and ObjectivesAcute myocardial infarction-related heart failure (HF) is associated with poor outcome. This study was designed to investigate the usefulness of global longitudinal strain (GLS), global circumferential strain (GCS) and mean longitudinal strain of left anterior descending artery territory (LSant) measured by 2-dimensional speckle tracking echocardiography (2D STE) in prediction of acute anterior wall ST-segment elevation myocardial infarction (ant-STEMI)-related HF.MethodsA total of 171 patients with ant-STEMI who underwent successful primary coronary intervention and had available 2D STE data were enrolled. Patients were divided into 3 groups: in-hospital HF, post-discharge HF, and no-HF groups.ResultsIn-hospital and post-discharge HF developed in 39 (22.8%) and 13 (7.6%) of patients, respectively and 113 patients (69.6%) remained without HF. Multivariate analysis showed that GLS was the only factor significantly associated with the development of in-hospital HF. For post-discharge HF, LSant was the only independent predictor. Other echocardiographic or laboratory parameters did not show independent association with the development of ant-STEMI-related HF.ConclusionsGLS is a powerful echocardiographic parameter related to development of in-hospital HF and LSant was significantly associated with post-discharge HF in patients with successfully reperfused ant-STEMI.

Revascularization of left anterior descending artery area using a skeletonized left internal mammary artery: a comparison between sequential and separate grafting

Objective: To evaluate in-hospital and mid-term outcomes of sequential versus separate grafting of in situ skeletonized left internal mammary artery (LIMA) to the left coronary system in a single-center, propensity-matched study. Methods: After propensity score matching, 120 pairs of patients undergoing first, scheduled, isolated coronary artery bypass grafting (CABG) with in situ skeletonized LIMA grafting to the left anterior descending artery (LAD) territory were entered into a sequential group (sequential grafting of LIMA to the diagonal artery and then to the LAD) or a control group (separate grafting of LIMA to the LAD). The in-hospital and follow-up clinical outcomes and follow-up LIMA graft patency were compared. Results: The two propensity score-matched groups had similar in-hospital and follow-up clinical outcomes. The number of bypass conduits ranged from 3 to 6 (with a mean of 3.5), and 91.3%(219/240)of the included patients received off-pump CABG surgery. No significant differences were found between the two propensity score-matched groups in the in-hospital outcomes, including in-hospital death and the incidence of complications associated with CABG (prolonged ventilation, peroperative stroke, re-operation before discharge, and deep sternal wound infection). During follow-up, 9 patients (4 patients from the sequential group and 5 patients from the control group) died, and the all-cause mortality rate was 3.9%. No significant difference was found in the all-cause mortality rate between the 2 groups[3.4% (4/116) vs 4.3% (5/115), P=0.748]. During follow-up period, 99.1% (115/116) patency for the diagonal site and 98.3% (114/116) for the LAD site were determined by coronary computed tomographic angiography after sequential LIMA grafting, both of which were similar with graft patency of separate grafting of in situ skeletonized LIMA to the LAD. Conclusions: Revascularization of the left coronary system using a skeletonized LIMA resulted in excellent in-hospital and mid-term clinical outcomes and graft patency using sequential grafting.

In-situ left-sided bilateral internal thoracic artery: elevated hemidiaphragm

Background Procurement of the internal thoracic artery risks ipsilateral phrenic nerve injury and elevated hemidiaphragm. Anatomical variations increase the risk on the right side. Patients receiving left-sided in-situ right internal thoracic artery configurations appear to be at greatest risk. Methods From 2014 to 2016, 432 patients undergoing left-sided in-situ bilateral internal thoracic artery grafting were grouped according to right internal thoracic artery configuration: retroaortic via transverse sinus (77%) or ante-aortic (23%); targets were the circumflex and left anterior descending artery territories, respectively. Elevated hemidiaphragm was assessed by serial chest radiographs and categorized by side, complete (≥2 intercostal spaces) versus partial, and permanent versus transient. Results Right elevated hemidiaphragm occurred in 4.2% of patients. The incidence of radiological complete right elevated hemidiaphragm was 2.8% (12/432); 8 cases were transient with recovery in 3.5 ± 0.3 weeks. Permanent right elevated hemidiaphragm occurred in 0.9% (retroaortic group only). Permanent left elevated hemidiaphragm occurred in 0.9% and was significantly higher in the ante-aortic group (3/99 vs. 1/333, p = 0.039). No bilateral hemidiaphragm elevation was documented. Partial right elevated hemidiaphragm occurred in 1.4% and was not associated with adverse early or late respiratory outcomes. Conclusions Despite susceptible right phrenic nerve-internal thoracic artery anatomy, the incidence of permanent right elevated hemidiaphragm is low and no higher than left-sided in prone bilateral internal thoracic artery subsets. This reflects skeletonized internal thoracic artery procurement. Although statistical significance was not achieved, a retroaortic right internal thoracic artery configuration may constitute a higher risk of right phrenic nerve injury.

A Rare Case of Single Right Coronary Artery with Absent Left Main Coronary Artery

A 54-year-old woman presented with abdominal pain and diarrhoea, and had new T-wave inversion on electrocardiogram in leads V2–V6. Past history included recurrent deep vein thrombosis/pulmonary embolism and a recent subtotal colectomy for ulcerative colitis. The patient denied chest pain and serial troponin I measurements were normal (<0.040 μg/L). Postoperative ileus was the likely cause of abdominal pain. Echocardiography revealed impaired left ventricular (LV) systolic function (LV ejection fraction 35–40%). Coronary angiography was performed and the left main coronary artery (LMCA) could not be located despite cuspal injections, ascending aortogram, and left ventriculogram. A dominant right coronary artery (RCA) was visualised, which passed around the left ventricular apex to the area normally supplied by the obtuse marginal, diagonal, and distal left anterior descending arteries. Computed tomography coronary angiography (CTCA) revealed a superdominant RCA supplying the LV apex and lateral wall with no LMCA coming off the left coronary cusp. The left circumflex was small and arose from a conus branch separate to the RCA. No significant stenosis was visualised on CTCA. The T-wave changes on electrocardiogram and subtle subendocardial enhancement/fibrosis in the anterior wall on cardiac magnetic resonance imaging were deemed to be secondary to supply–demand ischaemia, particularly at the distal end of the RCA, where it supplied the left anterior descending artery territory. The patient was discharged on metoprolol 25 mg twice daily and her usual warfarin. Single RCA with absent LMCA is extremely rare with only few isolated cases in the literature. Use of CTCA in combination with coronary angiography was useful in defining this unusual anatomy.

Case of a Large Dissecting Intramyocardial Hematoma Treated Conservatively

Case of a Large Dissecting Intramyocardial Hematoma Treated Conservatively

Evaluation of myocardial deformation in patients with Kawasaki disease using speckle-tracking echocardiography during mid-term follow-up.

We explored left ventricular mechanics using speckle-tracking echocardiography in 35 patients with a history of Kawasaki disease at least 6 months after the acute phase. We also included 30 healthy children as controls. Strain data sets were acquired for the quantification of left ventricular global strain, segmental strain, and left ventricular ejection fraction. The mean age of our patients was 25.6±15.4 months. At a median follow-up of 57.5 months (16.5-98.2), although both values were in the normal range, the mean left ventricular ejection proportion of patients (57.3%) was a little lower than that of controls (p⩽0.05). Patient strain values at the basal inferoseptal (20.0), basal anterolateral (19.5), apical septal (23.3), and apical inferior (24.0) segments were lower compared with controls. In all, seven patients had coronary aneurysms during follow-up. Kawasaki disease patients with pyuria had lower left ventricular strain at the mid anterior, mid anteroseptal, apical anterior, and apical inferior segments and global longitudinal strain compared with patients with no pyuria (p⩽0.05). In children with a history of Kawasaki disease, impairment of left ventricular mechanics occurs especially within the left anterior descending artery territories.

Cellular cardiomyoplasty into infracted swine's hearts by retrograde infusion through the venous coronary sinus: An experimental study.

The aim was to create a model of myocardial infarction with a borderline myocardial impairment which would enable evaluation of the retrograde cellular cardiomyoplasty through the venous coronary sinus in a large animal model. Fifteen (study group) and 10 juvenile farm pigs (control group) underwent distal left anterior descending artery ligation. One month later the study group animals underwent sternotomy and a murine myoblastic line C2-C12 was injected at a constant pressure of 30mmHg, into the coronary sinus. Thirty days later all animals that survived from both groups underwent transthoracic echocardiography and 99Tc scintigraphy and were later euthanized and specimens were taken for microscopic evaluation. Cardiac output decreased significantly after ligation (p<0.001) and increased significantly after cardiomyoplasty (p<0.001). In all animals, the surgical induction of myocardial infarction caused a marked decline in the echocardiographic values of cardiac function; however, the cardiac function and dimensions were significantly improved in the study group after cardiomyoplasty versus the control group. All animals undergoing cardiomyoplasty demonstrated a significant reduction of the perfusion deficit in the left anterior descending artery territory, instead such data remained unchanged in the control group. The histological examination demonstrated the engrafted myoblasts could be distinguished from the activated fibroblasts in the scar tissue because they never showed any signs of collagen secretion and fiber buildup. In conclusion, the venous retrograde delivery route through the coronary sinus is safe and effective, providing a significant improvement in function and viability.

INFLUENCE OF LEFT BUNDLE BRANCH BLOCK IN ASSESSMENT OF MYOCARDIAL BLOOD FLOW FROM RUBIDIUM 82 POSITRON EMISSION TOMOGRAPHY IMAGING

Perfusion defects are frequent in myocardial scintigraphy in left bundle branch block (LBBB) patients. However, scarce studies show decreased coronary flow reserve (CFR) in the left anterior descending artery territory, regardless of the presence of coronary artery disease (CAD). We sought to