Proximal Left Main Coronary Artery Research Articles

Evaluation of post-dilatation on longitudinal stent deformation and postprocedural stent malapposition in the left main artery by optical coherence tomography (OCT): an in vitro study

BackgroundThe diameter of the ostial and proximal left main coronary artery can be greater than 5.0 mm. However, the diameters of the mostly available coronary drug-eluting stents (DESs) are ≤ 4.0 mm. Whether high-pressure dilatation can increase the diameter of stents from 4.0 to 5.0 mm and whether post-dilatation leads to longitudinal stent deformation (LSD) of 4.0-mm-diameter stents have rarely been studied. Therefore, this study aims to evaluate LSD and stent malapposition of six types of commercially available 4.0-mm-diameter stents in China in a 5.0-mm-diameter artificial blood vessel model by optical coherence tomography (OCT) in vitro.MethodsThe left main coronary artery was simulated by a truncated cone-shaped silicone tube. The internal diameters were 4.0 mm at one end of the silicone tube and 5.0 mm at the other end. Six different types of coronary stents widely used in China were selected for this study. Each stent was respectively implanted into the simulated blood vessel and dilated to a diameter of 4.2 mm according to the stent-balloon pressure compliance table. The stents were subjected to post-dilatation with a 5.0 × 15-mm noncompliant balloon. The LSD ratio of the longitudinal axis of each stent and stent malapposition were measured through OCT, and any fractures of the stents were determined.ResultsNone of the six types of stents fractured following post-dilatation. The longitudinal axes of the BuMA and Excrossal stents were slightly shortened, while the other stents were elongated after high-pressure post-dilatation. All stents expanded to a diameter of 5.0 mm without incomplete stent apposition, except for the Nano Plus stent, which remained malapposed after high-pressure post-dilatation.ConclusionAll 4.0-mm-diameter stents can be expanded to a diameter of 5.0 mm by noncompliant balloon post-dilatation without stent strut fracture. Most stents were found to be well apposed after high-pressure post-dilatation. However, LSD was observed after post-balloon dilatation. Stent malapposition might be positively correlated with the percentage change in stent length.

Abstract 15578: A Rare Case of Anomalous Left Main Coronary Artery Origin Presenting as ST Elevation Myocardial Infarction

Background: ST-segment elevation myocardial infarctions (STEMI) are uncommon presentations of coronary artery anomalies and pose challenges in the emergent setting of percutaneous coronary interventions. We describe an extremely rare case of left main coronary artery (LMCA) originating off the right coronary artery (RCA) in a patient who presents with STEMI and was found to have Medina 1,1,1 lesion at the origin of the anomalous (LMCA). Case Presentation: An 81-year old male, with a past medical history significant for aortic stenosis and hyperlipidemia, presents to the emergency room for substernal non-radiating chest pressure. His electrocardiogram showed ST segment elevations in inferior and anterior leads. He was taken emergently to the cardiac cath lab. Coronary angiogram revealed a single right coronary ostium with an anomalous LMCA to mid left anterior descending (LAD) artery via dual insertion within a myocardial bridge. There was severe 90% Medina 1,1,1 bifurcating proximal RCA stenosis and 90% proximal LMCA stenosis. The entire left coronary system was fed by the anomalous LMCA, which was inserted into the mid-LAD in a dual insertion, between which there was a myocardial bridge. Cardiothoracic surgery team was consulted, and decision was made to pursue coronary artery bypass grafting (CABG). An intra-aortic balloon pump was placed via right femoral artery and patient was taken for emergent surgery, where he underwent 3 vessel CABG (left internal mammary artery to LAD, saphenous venous graft to obtuse marginal branch and posterior descending artery). Discussion: A broad spectrum of coronary anomalies have been reported, but their incidence in STEMI is rare. We discuss a very rare anomaly in which the entire left coronary system branches off the RCA, and culprit lesion was found to be a Medina 1,1,1 lesion. We aim to add to the sparce data pool of STEMI management in patients with anomalous coronary arteries.

C57. Left Main Coronary Artery Compression by A Dilatated Pulmonary Artery in Patients with Pulmonary Arterial Hypertension: What Should We Do?

Abstract Background Pulmonary artery hypertension (PAH) is often associated with angina and extrinsic compression of left main coronary artery (LMCA) by a dilatated pulmonary artery is recognized as the cause. The optimal management for pulmonary arterial hypertension with extrinsic LMCA compression has not been clearly established. Case Summary We report on 31-year-old female with secundum atrial septal defect and 44 -year-old female with incomplete atrioventricular septal defect complain of progressive typical angina that aggravated with exertion. The electrocardiogram showed right heart strain and chest radiograph showed cardiomegaly involving the right cavities with enlargement of the pulmonary arch. Right heart catheterization showed pulmonary arterial hypertension with the mean pulmonary artery pressure of 61 mmHg and 65 mmHg respectively. Cardiac CT demonstrated compression of proximal LMCA by dilatated pulmonary artery. Although with optimal phosphodiesterase-5 (PDE5) inhibitor and prostacyclin analog therapy, patients still complain of angina. Discussion LMCA compression may be associated with additional complications of severe myocardial ischemia, including myocardial infarction, left ventricle dysfunction, arrhythmia, and eventually, sudden death. It may occur in patients with PAH with severely dilated PA and can be identified with either computed tomographic coronary angiography or selective coronary angiography. Furthermore, there are no guidelines recommending optimal management of this disease entity. Optimalization of pharmacologic treatment of PAH may reduce compression-related symptoms. A stent implantation is a promising alternative option for the treatment of LMCA compression and provides an optimal risk-to-benefit ratio, both for symptom relief and for long-term outcomes.

C57. Left Main Coronary Artery Compression by A Dilatated Pulmonary Artery in Patients with Pulmonary Arterial Hypertension: What Should We Do?

Abstract Background Pulmonary artery hypertension (PAH) is often associated with angina and extrinsic compression of left main coronary artery (LMCA) by a dilatated pulmonary artery is recognized as the cause. The optimal management for pulmonary arterial hypertension with extrinsic LMCA compression has not been clearly established. Case Summary We report on 31-year-old female with secundum atrial septal defect and 44 -year-old female with incomplete atrioventricular septal defect complain of progressive typical angina that aggravated with exertion. The electrocardiogram showed right heart strain and chest radiograph showed cardiomegaly involving the right cavities with enlargement of the pulmonary arch. Right heart catheterization showed pulmonary arterial hypertension with the mean pulmonary artery pressure of 61 mmHg and 65 mmHg respectively. Cardiac CT demonstrated compression of proximal LMCA by dilatated pulmonary artery. Although with optimal phosphodiesterase-5 (PDE5) inhibitor and prostacyclin analog therapy, patients still complain of angina. Discussion LMCA compression may be associated with additional complications of severe myocardial ischemia, including myocardial infarction, left ventricle dysfunction, arrhythmia, and eventually, sudden death. It may occur in patients with PAH with severely dilated PA and can be identified with either computed tomographic coronary angiography or selective coronary angiography. Furthermore, there are no guidelines recommending optimal management of this disease entity. Optimalization of pharmacologic treatment of PAH may reduce compression-related symptoms. A stent implantation is a promising alternative option for the treatment of LMCA compression and provides an optimal risk-to-benefit ratio, both for symptom relief and for long-term outcomes.

Percutaneous Approach for Late Left Main Coronary Detachment Resulting in Aortic Pseudoaneurysm After Bentall Procedure

We describe the case of 35-year-old patient with known Marfan syndrome, and previously treated by a Bentall procedure, who presented with an aortic pseudoaneurysm secondary to a partial proximal left main coronary artery detachment fixed by covered stent implantation. (Level of Difficulty: Advanced.)

Three-dimensional optical coherence tomography versus intravascular ultrasound in percutaneous coronary intervention for the left main coronary artery.

We aimed to compare the intravascular imaging findings, and clinical outcomes between three-dimensional optical coherence tomography (OCT)- and intravascular ultrasound (IVUS)-guided percutaneous coronary intervention (PCI) for the left main coronary artery (LMCA). We enrolled 331 patients underwent OCT- or IVUS-guide single crossover stenting across the side branch (SB) and subsequent kissing balloon inflation (KBT) for LMCA bifurcation. Primary endpoint was defined as a composite of cardiac death, myocardial infarction, and target lesion revascularization. Of 331 patients, 58 patients (17.5%) underwent OCT-guide PCI. OCT-guide PCI associated with higher frequency of proximal optimization technique (POT) (98.3% vs 85.3%, P = 0.013) and smaller balloon size of POT (4.29 ± 0.44mm vs 4.43 ± 0.42, P = 0.02) than IVUS-guide PCI. Although maximal stent area at LMCA and minimal stent area at main vessel were significantly smaller in OCT-guide PCI in intravascular imaging (P = 0.01, and P = 0.002, respectively), the restenosis rate at follow-up angiography was comparable in both groups (15.2% vs. 9.4%, P = 0.387). Cumulative rate of primary endpoint was not significantly different between 2 groups both before and after propensity score adjustment (7.0% vs. 7.4%, P = 0.98 and 2.6% vs. 7.3%, P = 0.18). In conclusion, the clinical outcomes at 1year were comparable, suggesting OCT- and IVUS-guided PCI for LMCA were similarly feasible. The balloon size of POT in OCT-guide PCI might be influenced by the limited visibility in the proximal LMCA.

AN ACUTE MYOCARDIAL INFARCTION CAUSING A MOTOR VEHICLE ACCIDENT OR THE MOTOR VEHICLE ACCIDENT CAUSING AN ACUTE MYOCARDIAL INFARCTION: A CLINICAL DILEMMA

SESSION TITLE: Medical Student/Resident Cardiovascular Disease Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: October 18-21, 2020 INTRODUCTION: Acute myocardial infarction is seen in very few patients (0.5%) who are admitted post-motor vehicle accidents (MVAs) (1). It is, however, one of the common natural causes of incapacitation leading to MVA (2). We present a case of a male, who suffered a V-fib cardiac arrest post-MVA and was subsequently diagnosed with a 99 percent occlusion of the proximal left main coronary artery. CASE PRESENTATION: A 68-year old male known to have hypertension was brought to the ED after a head-on motor vehicle collision. EMS reported that the patient self-extricated from the vehicle, walked on the sidewalk, and fell unconscious afterward with V-fib arrest. The patient achieved ROSC after one round of CPR with cardioversion, and 1mg epinephrine. Due to low GCS, he was intubated and transferred to ICU. His labs were significant for elevated white blood cells and troponin of 0.14 (normal<0.03). EKG showed sinus rhythm with non-specific ST-T wave changes in Leads I, aVL, V5, and V6. CT chest showed non-displaced multiple ribs and sternal fractures with small retrosternal hematoma. TTE demonstrated a 25-30% ejection fraction and multiple wall motion abnormalities with apical ballooning. The patient was extubated after his respiratory status showed signs of improvement. Meanwhile, since the troponin levels continued to rise (0.14 < 1.93 < 3.62 < 6.89 < 7.02), heparin drip was started. Although the patient was finally alert and oriented, he had amnesia of the event. However, he denied having any chest pain, or anginal symptoms before the accident. Our differential diagnoses were cardiac injury from either accident or CPR, Takostubo cardiomyopathy, or myocardial infarction. His repeat EKG was different from the one on arrival and showed biphasic T-wave in V2 -V3 and symmetric T-wave inversion in V4-V6. On the second day of his hospital stay, cardiac catheterization was performed that showed 99% proximal LAD stenosis, leading to percutaneous coronary intervention. His status slowly improved and was discharged on a life vest with a follow up with a cardiologist. DISCUSSION: While myocardial injury post blunt trauma, associated with MVAs, are common, thrombotic occlusions are rare. Unlike our case, in a few of the reported cases of thrombotic occlusion, (3) (4) the patients were fairly young. The presentations of the case poised a clinical dilemma because we could not establish if MI caused the MVA or vice-versa. Also, coronary thrombosis was not the top differential diagnosis in this case given the trauma, CPR, rib fractures, and TTE findings. Regardless, a timely cardiac catheterization with revascularization was performed, and the patient recovered. CONCLUSIONS: Acute myocardial infarction should always be one of the differential diagnoses after cardiac injury associated with trauma as timely cardiac catheterization and revascularization can be life-saving. Reference #1: 1.Alkhouli M, Alqahtani F. Incidence and outcomes of acute myocardial infarction during motor vehicle accident related hospitalizations. The American journal of cardiology. 2019 Mar 1;123(5):725-8. Reference #2: 2. Antecol DH, Roberts WC. Sudden death behind the wheel from natural disease in drivers of four-wheeled motorized vehicles. The American journal of cardiology. 1990 Dec 1;66(19):1329-35. Reference #3: 3.Watt AH, Stephens MR. Myocardial infarction after blunt chest trauma incurred during rugby football that later required cardiac transplantation. Heart. 1986 Apr 1;55(4):408-10. 4.Calvo Orbe L, Garcia Gallego F, Sobrino N, Sotillo J, Lopez-Sendon JL, Oliver J, Coma I, Frutos A, Sobrino JA, Navarro JM. Acute myocardial infarction after blunt chest trauma in young people: need for prompt intervention. Catheterization and cardiovascular diagnosis. 1991 Nov;24(3):182-5. DISCLOSURES: No relevant relationships by Abhishek Kalidas Kulkarni, source=Web Response No relevant relationships by Odalys Lara-Garcia, source=Web Response No relevant relationships by Ruby Maini, source=Web Response No relevant relationships by Priyanka Parajuli, source=Web Response No relevant relationships by Manjari Regmi, source=Web Response No relevant relationships by Mohsin Salih, source=Web Response No relevant relationships by Nitin Tandan, source=Web Response

The feasibility of surgical patch osteoplasty in isolated left main coronary stenosis.

Background: Coronary artery bypass grafting (CABG) is perceived as the most common treatment for left main coronary artery (LMCA) disease with good results compared to left-main stenting or medical therapy. Surgical patch angioplasty (SPA) may present a substitute to the standard CABG in patients with isolated LMCA disease, and it offers physiological antegrade myocardial perfusion, keeps ostial patency and saves bypass material. The objective of this study is to demonstrate the feasibility of patch osteoplasty in patients with isolated LMCA stenosis.&#x0D; Methods: This is a retrospective study performed on eight patients with angiographically proven ostial or proximal LMCA stenosis who underwent surgical patch angioplasty. Two of them had associated right coronary artery bypass grafting. All patients were performed with cardiopulmonary bypass and saphenous vein patch. An anterior approach with transverse aortotomy was utilized in all cases. Patients were followed-up clinically for a mean period of 14 months (ranging from 26 to 6 months) for recurrence of symptoms and any postoperative complications.&#x0D; Results: The early postoperative period was uneventful in all patients. No perioperative mortality was reported. Two patients had postoperative atrial fibrillation, and one patient with poor left ventricular function required preoperative intra-aortic balloon pump. Angiography was done in the first three cases, and all showed no restenosis and no vein patch dilatation.&#x0D; Conclusion: Surgical patch angioplasty may be a safe and suitable alternative to CABG in selected patients with isolated ostial LMCA stenosis. Further studies are needed to compare the results of the SPA with those of standard CABG and LMCA stenting.

Abstract 235: Revascularization Patterns of Systolic Heart Failure in a Large Urban County Hospital

Background: Coronary angiography is frequently performed after the initial diagnosis of heart failure to determine etiology and revascularization strategy. Current body of evidence suggests that surgical revascularization conveys a mortality benefit as compared to medical therapy alone, and the role of percutaneous coronary intervention (PCI) is not yet established. The aim of this study is to describe revascularization patterns among patients presenting with systolic heart failure who underwent diagnostic angiography at a large urban county hospital. Methods: We evaluated patients presenting to the emergency department with symptomatic heart failure with reduced ejection fraction (HFrEF) without acute coronary syndrome (n=150; average left ventricular ejection fraction of 25%) who underwent coronary angiography between January 2011 and January 2015. We defined surgical coronary artery disease (CAD) as: 1) three-vessel disease, 2) two-vessel disease including the proximal LAD artery, or 3) two-vessel disease including the left main coronary artery. Primary outcomes included intervention (PCI, CABG, or medical therapy [MT] alone) as well as referral for CABG. Results: Of patients presenting with HFrEF who underwent diagnostic angiography, 80% (n=120) of patients had obstructive CAD with 36% (n=43) of those patients having surgical CAD. Of those with surgical CAD, 74% (n=32) underwent PCI, 18% (n=8) underwent CABG and 7% (n=3) received MT alone. Of patients with 1-vessel CAD, or 2-vessel CAD without involvement of the proximal LAD artery or left main coronary artery, 81% (n=63) underwent PCI while 19% (n=14) received MT alone. Conclusion: Patients presenting with symptomatic HFrEF referred for cardiac catheterization have a high prevalence of obstructive CAD. Most patients with evidence of either surgical or non-surgical CAD during coronary angiography underwent revascularization, with PCI being the dominant revascularization method.

A volumetric intracoronary ultrasonographic study of coronary bifurcation lesions.

To evaluate the plaque distribution and composition pattern in the left main coronary artery (LMCA) disease using intracoronary ultrasound. Intravascular ultrasound data of 50 patients from the January 2010 to December 2015 with significant LMCA bifurcation lesions, with angiographic diameter stenosis >50%, and requiring revascularization, were evaluated. Plaque burden and percentage of necrotic core (% NC) at the minimal lumen area site and maximal % NC site were measured in different segments. The segments that were included in the study are as follows: segment 1: proximal LMCA, segment 2: left anterior descending (LAD) ostium, segment 3: left circumflex branch (LCX) ostium, segment 4: proximal LAD, segment 5: proximal LCX. According to its relationship with the bifurcation ridge, the blood vessel wall was divided into the contralateral bifurcation ridge blood vessel wall and bifurcation ridge blood vessel wall. Plaque burden results showed that the plaque eccentricity index of segment 2 and segment 3 was significantly higher than that of the other segments at sites of the minimal lumen area and maximal % NC with a statistically significant difference (p<0.05). Plaque eccentricity index of contralateral bifurcation ridge was significantly higher than that of the bifurcation ridge, and the difference was statistically significant (p<0.05). Analysis of plaque composition showed the fibrous tissue percentage of segment 2 and segment 3 was significantly higher than the other segments that at the sites of minimal lumen area and the maximal % NC site. The fibrous percentage of the contralateral bifurcation ridge was significantly lower than that of the bifurcation ridge. Intravascular ultrasound is an effective way for detecting the distribution and composition of the atherosclerotic plaque at the left main coronary artery bifurcation and is of great significance to adjuvant interventional therapy.

Plaque composition and morphologic characteristics in significant left main bifurcation disease; virtual histology intravascular ultrasound study.

Although the left main coronary artery (LMCA) is clinically the most important site, little is known about the longitudinal plaque distribution and composition in the significant LMCA disease. Preprocedure virtual histology intravascular ultrasound data were analyzed in 120 patients with significant LMCA bifurcation lesions (angiographic diameter stenosis>50%) requiring revascularization. Plaque burden and percentage of necrotic core (%NC) at the minimal lumen area site and maximal %NC site were measured in four segments: proximal LMCA, distal LMCA, left anterior descending (LAD) ostium, and proximal LAD. Angiographically, a significant LMCA and ostial LAD stenosis were observed in 89.2 and 81.7% of patients, respectively. At the minimal lumen area site, the proximal LAD segment showed the smallest lumen [3.5 mm (2.5-4.7), P<0.001] and the greatest plaque burden [73.2% (63.0-79.3), P<0.001] compared with the other segments. Also, there was a significant downward trend in the number of IVUS-defined lesions toward the proximal LMCA (P=0.001). At the maximal %NC site, the proximal LAD segment carried the largest necrotic core [32.7% (25.7-40.1), P<0.001] and the most frequent virtual histology thin-cap fibroatheroma (67.6%, P<0.001) among the segments, followed by the proximal LMCA [30.3% (22.3-40.0) and 32.9%, respectively]. Most of the plaques carried, at least, one slice of fibroatheroma in every segment; thus, fibroatheroma distributed in a continuous pattern from the proximal LAD to the proximal LMCA. In the significant LMCA bifurcation disease, the proximal LAD segment was found to have the smallest lumen, the largest plaque burden, the highest virtual histology thin-cap fibroatheroma rate, and thus presented the most vulnerable characteristics by virtual histology intravascular ultrasound.

Coronary Computed Tomographic Angiography at 80 kVp and Knowledge-Based Iterative Model Reconstruction Is Non-Inferior to that at 100 kVp with Iterative Reconstruction.

The aims of this study were to compare the image noise and quality of coronary computed tomographic angiography (CCTA) at 80 kVp with knowledge-based iterative model reconstruction (IMR) to those of CCTA at 100 kVp with hybrid iterative reconstruction (IR), and to evaluate the feasibility of a low-dose radiation protocol with IMR. Thirty subjects who underwent prospective electrocardiogram-gating CCTA at 80 kVp, 150 mAs, and IMR (Group A), and 30 subjects with 100 kVp, 150 mAs, and hybrid IR (Group B) were retrospectively enrolled after sample-size calculation. A BMI of less than 25 kg/m2 was required for inclusion. The attenuation value and image noise of CCTA were measured and the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated at the proximal right coronary artery and left main coronary artery. The image noise was analyzed using a non-inferiority test. The CCTA images were qualitatively evaluated using a four-point scale. The radiation dose was significantly lower in Group A than Group B (0.69 ± 0.08 mSv vs. 1.39 ± 0.15 mSv, p < 0.001). The attenuation values were higher in Group A than Group B (p < 0.001). The SNR and CNR in Group A were higher than those of Group B. The image noise of Group A was non-inferior to that of Group B. Qualitative image quality of Group A was better than that of Group B (3.6 vs. 3.4, p = 0.017). CCTA at 80 kVp with IMR could reduce the radiation dose by about 50%, with non-inferior image noise and image quality than those of CCTA at 100 kVp with hybrid IR.

Intracoronary thrombus formation on a guide wire: who is to blame?

Case report: A 77-year-old man with stable angina and known left main coronary artery (LMCA) disease was admitted for elective percutaneous coronary intervention (PCI). Dual antiplatelet therapy with aspirin and clopidogrel had been instituted 7 days before the PCI, accompanied by administration of unfractionated heparin (UHF) during the procedure. For the PCI planning purpose, intravascular ultrasound was performed to evaluate the anatomy and the size of the LMCA and the morphology of the left anterior descending artery-first diagonal (LAD-D1) bifurcation lesion that had appeared only moderately stenotic on angiography. Minimal lumen diameter of the middle LAD segment and LMCA was 1.6 mm and 2.6 mm, respectively, indicating the severity of both lesions. After predilatation with the semicompliant balloon, a successful provisional stenting of the LAD-D1 bifurcation lesion using drug-eluting stent (DES) was performed, followed by high-pressure postdilatation to optimize stent deployment. At that time, the thrombus formation on a guide wire within the LMCA was noted, giving rise to distal LAD embolization. Direct stenting of the proximal LMCA with DES 4.0/9 mm was then performed and the intracoronary bolus of eptifibatide was given, leading to complete LMCA thrombus resolution, with residual thrombi seen in the distal LAD segments. Due to chest pain aggravation, a second-look angiography was performed 2 hours after the index procedure, showing non-occlusive dissection at the distal end of the LMCA stent. Additional DES 4.0/9 mm was implanted with optimal result and Thrombolysis In Myocardial Infarction 3 flow. Clopidogrel was replaced with ticagrelor. The 6-month follow-up was uneventful. Discussion: Pharmacotherapy during PCI is used to mitigate the sequel of iatrogenic plaque rupture and to reduce the risk of thrombus formation on intravascular PCI equipment. Iatrogenic damage to the endothelium leads to increased expression of tissue factor and activation of the coagulation cascade, ultimately leading to thrombus formation 1

Stent Implantation of Left Main Coronary Artery Stenosis in an Infant—Effective Long-Term Treatment?

Coronary artery stenosis is a rare phenomenon in children. Coronary stent implantation is generally not considered a standard treatment option due to technical difficulties and potential complications in this group of patients. Nevertheless, several pediatric cases reporting successful implantation with acceptable short-term experiences have been described. The following case presents a successful stent implantation for left main coronary artery (LMCA) stenosis early after surgery for anomalous left coronary artery from pulmonary artery (ALCAPA) at the age of 6 months. The excellent mid-term results and notably the procedure's potential as a longterm treatment in small children are highlighted. A 6-month-old infant underwent surgery for ALCAPA. Due to sudden postoperative deterioration, cardiac catheterization was performed. Coronary angiography revealed severe (90%) ostial LMCA stenosis. A PROMUS drug-eluting stent (Promus Element AL3.0 × 8 mm, Boston Scientific, Natick, Massachusetts, USA) was implanted. The procedure was performed without complications. Antiplatelet therapy with acetylsalicylic acid and clopidogrel was initiated. Subsequently, cardiac function improved slowly. Cardiac catheterization 3 years 8 months after stent implantation showed no restenosis with a proximal LMCA diameter still at the 50(th) percentile for age. Neither were signs of heart failure reported at the last follow-up at 7 years of age. Presupposing normal growth, the implanted stent would thus provide sufficient myocardial perfusion with a LMCA lumen at the 40(th) percentile at the age of 16 years. In selected cases, coronary stent implantation may be an effective mid- to long-term treatment of coronary artery stenosis even in very young children.

Chronic rupture of the coronary sinus of Valsalva with pseudoaneurysm formation.

A 45-year-old male with no significant medical history or risk factors for coronary disease presented with a 1-year history of intermittent, exertional chest pain radiating to the neck. Physical examination was unremarkable. An EKG was normal. A chest X-ray, however, revealed a 4-cm round focus with peripheral calcification overlying the left side of the heart. A computed tomography (CT) of the chest revealed a spherical area with rim calcification in the area of the aortic root on the left. The differential diagnosis at that point was: a calcified left coronary artery aneurysm, left ventricular anterior wall calcified pseudoaneurysm or a pseudoaneurysm arising from the left aortic root. This prompted a CT angiogram of the coronary arteries. His coronary arteries all appeared normal on imaging, but the calcified mass was localized to have originated from the left coronary sinus of Valsalva. It appeared to be a ruptured aneurysm of the left coronary sinus, which led to the formation of a pseudoaneurysm with peripheral calcification. It was felt that the process was chronic due to the long history of angina and calcification present within the sac. The superior margin of the neck of the pseudoaneurysm was 2 mm inferior to the origin of the left coronary artery, and the inferior margin was contiguous with the hinge point of the left leaflet (Fig. 1A). Figure 1: (A) Coronal, axial and sagittal views of a CT angiogram showing a chronically ruptured left sinus of Valsalva contained within a calcified pseudoaneurysm. (B) 3D reconstruction of the heart and coronary arteries demonstrating the relationship between ... His symptoms were thought to be related to external compression of the proximal left main coronary artery (LMCA; Fig. 1B). To better assess the aortic root and coronary arteries, the patient underwent cardiac catheterization, which confirmed the finding of normal coronary arteries, but revealed displacement of the LMCA due to mass effect from the pseudoaneurysm (Fig. 1C—left). Selective angiography of the aortic root and left coronary sinus revealed a thick layer of organized thrombus within the sac without fistulization (Fig. 1C—right). It was recommended he undergoes surgical resection and repair to prevent further complications, including hemodynamically significant rupture, fistula formation or heart failure, but the patient refused to undergo operative management. True aneurysms of the sinus of Valsalva (ASVs) are either congenital or acquired. Congenital ASVs are rare anomalies most often caused by the absence of muscular and elastic tissue in the aortic wall behind the sinus of Valsalva. Acquired ASVs are caused by conditions that affect the integrity of the aortic wall such as infections (e.g. bacterial endocarditis, syphilitic aortitis or tuberculosis), degenerative disease (e.g. atherosclerosis and connective tissue disease) or trauma. Most ASVs originate from the right coronary sinus (94%), and a minority originates from the non-coronary sinus (5%). Very rarely is the left coronary sinus affected [1, 2]. Pseudoaneurysms—or false aneurysms—are formed when a break in the intimal layer of the sinus causes blood to collect within a false lumen covered by the outer adventitia. They are more likely to occur due to localized intimal disease or trauma during procedures or surgeries. In many cases, a true aneurysm is present before the tear occurs [3, 4]. Obstruction of coronary flow secondary to aneurysms or pseudoaneurysms of the sinus of Valsalva is an uncommon manifestation. The risk of flow disturbance is substantially greater when the left coronary sinus is involved causing compression of the LMCA, left anterior descending and/or left circumflex artery [3, 5, 6].

Radiation and contrast agent doses reductions by using 80-kV tube voltage in coronary computed tomographic angiography: A comparative study

ObjectiveTo investigate the effects of 80-kilovoltage (kV) tube voltage coronary computed tomographic angiography (CCTA) with a reduced amount of contrast agent on qualitative and quantitative image quality parameters and on radiation dose in patients with a body mass index (BMI) <23.0kg/m2. MethodsOne hundred and twenty consecutive patients with a BMI <23.0kg/m2 and a low calcium load undergoing retrospective electrocardiogram (ECG)-gated dual-source CCTA were randomized into two groups [standard-tube voltage (120-kV) vs. low-tube voltage (80-kV)]. The injection flow rate of contrast agent (350mgI/mL) was adjusted to body weight of each patient (4.5–5.5mL/s in the 120-kV group and 2.8–3.8mL/s in the 80-kV group). Radiation and contrast agent doses were evaluated. Quantitative image quality parameters and figure of merit (FOM) of coronary artery were evaluated. Each coronary segment was evaluated for image quality on a 4-point scale. ResultsCompared with the 120-kV group, effective dose and amount of contrast agent in the 80-kV group were decreased by 57.8% and 30.5% (effective dose:2.7±0.5vs. 6.4±1.3mSv; amount of contrast agent:57.1±3.2 vs. 82.1±6.1mL; both p<0.0001), respectively. Image noise was 22.7±2.1HU for 120-kV images and 33.2±5.2HU for 80-kV images (p<0.0001). Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) in the proximal right coronary artery (RCA) and left main coronary artery (LMA) were all lower in 80-kV than 120-kV images (SNR in the proximal RCA: 16.5±1.8 vs. 19.4±2.8; SNR in the LMA: 16.3±2.0 vs.19.6±2.7; CNR in the proximal RCA: 19.4±2.3 vs.22.9±3.0; CNR in the LMA: 18.8±2.4 vs. 22.7±2.9; all p<0.0001). FOM were all significantly higher in 80-kV than 120-kV images (proximal RCA: 146.7±45.1 vs. 93.4±32.0; LMA: 139.1±47.2 vs. 91.6±31.1; all p<0.0001). There was no significant difference in image quality score between the two groups (3.3±0.8 vs. 3.3±0.8, p=0.068) despite decreased SNR and CNR of coronary artery in the 80-kV group. ConclusionThe 80-kV protocol significantly reduces radiation and contrast agent doses in CCTA in patients with a low BMI <23.0kg/m2 and a low calcium load while maintaining image quality.

Stenting of a left main coronary artery compressed by dilated pulmonary artery

A 54-year-old obese man without comorbidity presented with dyspnea associated with typical angina. Physical examination revealed jugular venous distension, systolic murmur at left parasternal border with a prominent pulmonary component of S2 and S3 gallop. He had ST depression throughout the precordial leads and troponin level of 8. Coronary angiography showed 95% narrowing in the proximal left main coronary artery (LMCA) with TIMI grade 3 flow (Image A, B, C). Echocardiography showed a markedly dilated pulmonary. CT angiography demonstrated compression of the LMCA by the severely enlarged Main pulmonary artery (MPA) (9.8×9.0 cm). Right heart catheterization revealed right ventricle pressure of 69/10 mmHg with mean pressure of 33 mmHg and right pulmonary artery pressure of 66/28 mmHg with mean pressure of 40 mmHg. Work up for the cause of pulmonary hypertension was consistent with primary pulmonary arterial hypertension (PPAH). Stent of the LMCA was performed with 4.5×12 mm bare metal Veriflex™ stent (Boston Scientific Company, Minneapolis, MN) with post-dilation diameter of 5mm.(Image D) Subsequently IVUS revealed adequate expansion of the stent and complete coverage of the lesion.(Image E) After the procedure, the patient reported immediate relief of symptoms. Optimal medical management was continued. Follow-up coronary angiography at 3 months showed a nonstenosed stent (Image F) and at 1 year, he remained asymptomatic. ![Figure][1] Figure 1. Angiographic and IVUS images LMCA compression by dilated MPA in PAH may not be uncommon as previously thought. It is a reversible cause of chest pain associated with PPAH. Traditionally, LMCA stenosis treatment involves coronary bypass graft surgery. However, LMCA stenosis secondary to compression by dilated MPA has been increasingly treated by angioplasty with promising outcome [1]: pending:yes

Use of hypophysin in hypotensive patients with low systemic vascular resistance following cardiopulmonary bypass

This study aimed to test the effects of hypophysin on hemodynamics and coronary artery caliber of patients with hypotension and decreased systemic vascular resistance (SVR) following cardiopulmonary bypass (CPB). Twenty-four patients with mean arterial pressure (MAP) < 60 mmHg, mean aorta pressure < 70 mmHg, SVR < 800 dynes.sec.cm-5, cardiac index (CI) > 2.5 l.min-1.m-2, central venous pressure > 8 mmHg and refractory to dopamine, norepinephrine, and fluid resuscitation were treated with hypophysin at an initial dose of 0.6 IU and a continuous infusion rate of 1 - 4 IU/h till the end of operation. The hemodynamics and the diameter of proximal left main coronary artery were evaluated before incision, before hypophysin administration, 5 min after hypophysin administration, and at the end of operation. MAP, SVR, and the diameter of proximal left main coronary artery increased whereas heart rate, CI, stroke volume index, and mean pulmonary artery pressure had no significant changes after hypophysin administration compared with before hypophysin administration. All hypophysin-treated patients successfully recovered. Hypophysin may improve the hemodynamics and dilate the proximal left main coronary artery in hypotensive patients with low SVR following CPB.

Left Main Coronary Artery Compression Long Term After Repair of Conotruncal Lesions: The Bow String Conduit

We report 4 cases of left main coronary artery (LMCA) compression after remote repair of conotruncal lesions and their successful surgical management.

Abstract 251: Clinical Symptoms and Angiographic Findings of Patients Undergoing Percutaneous Coronary Intervention without Prior Stress Testing: Insights from the NCDR

Background: Many patients undergoing elective percutaneous coronary intervention (PCI) do not have prior stress testing. It is unknown if these patients have more severe angina or obstructive coronary artery disease (CAD), whereby proceeding directly to PCI would represent sound clinical judgment and efficient use of resources. Methods: We identified elective PCIs performed between 1/1/09 - 3/31/11 in the NCDR CathPCI Registry ® and assessed for differences in angina (CCS class) and severity of CAD in those with and without pre-procedural stress testing. To further understand whether proceeding to PCI without prior stress testing could be justified because of a high pre-test probability for obstructive CAD (e.g., &gt;70% stenosis in an epicardial coronary artery), we evaluated cardiac catheterizations performed within the registry during the same period to assess the diagnostic yield of obstructive CAD in patients with and without prior stress testing. Results: Of 246,629 elective PCIs, 89,084 (36.1%) were performed without prior stress testing. A substantial proportion of both groups undergoing PCI were asymptomatic (no stress test group: 28.9% vs. stress test group: 30.7%), with only a modest difference in the frequency of CCS class III/IV angina (16.2% vs. 11.9%; Table). No meaningful differences in the frequency of proximal LAD (29.7 % vs. 29.9%), left main (5.6% vs. 7.2%) or 3-vessel coronary artery disease (21.1% vs. 19.5%) were observed in the 2 PCI groups. Moreover, the diagnostic yield for obstructive CAD on cardiac catheterization for patients without prior stress testing (n=462,611) was 35.4%, as compared with 58.0%, 38.8%, and 24.1% for those with severe, moderate, and mild ischemia, on pre-procedural stress testing. Conclusion: For elective PCI, the current practice of proceeding to coronary angiography and PCI without prior stress testing does not identify higher risk coronary anatomy or more symptomatic patients and may not improve diagnostic yield.