The de Winter ECG pattern: Distribution and morphology of ST depression.

BACKGROUND: The reported positive predictive value (PPV) for the "de Winter ECG pattern" to predict an acute left anterior descending artery (LAD) lesion is inconsistent. Besides, the morphology of upsloping or nonupsloping ST depression (STD) may have different significance of severity and prognostication. METHODS: We searched the MEDLINE database using "de Winter" or "junctional ST-depression with tall symmetrical T-waves" or "tall T wave" or "STEMI equivalent" as the item up to March 2020. We compared the ECG differences between the different culprit arteries and various morphological STD. RESULTS: A total of 70 patients with analyzable ECGs were included. In 60 patients (LAD group), the LAD was the culprit artery, while in 10 patients (non-LAD group), there were other etiologies. Maximal STD in V2 or V3 had a PPV of 89% of all patients and 98% of patients without ST elevation in V2 to detect an acute LAD lesion. The presence of q/Q-wave or poor R-wave progression in the precordial leads was significantly more often found in patients with upsloping STD than in patients with nonupsloping STD in the LAD group (84% vs. 27%, p < .01). In 18 patients, the ECG showed a change from upsloping to nonupsloping STD from the leads with maximal STD to the surrounding leads with less STD. CONCLUSIONS: The location of the maximal STD in the precordial leads differs between patients with LAD as the culprit artery and other etiologies of the de Winter ECG pattern. Upsloping STD signifies more severe signs of ischemia than nonupsloping STD.

Ischemic QRS prolongation as a biomarker of myocardial injury in STEMI patients.

BACKGROUND: Patients with acute coronary occlusion (ACO) may not only have ischemia-related ST-segment changes but also changes in the QRS complex. It has recently been shown in dogs that a greater ischemic QRS prolongation (IQP) during ACO is related to lower collateral flow. This suggests that greater IQP could indicate more severe ischemia and thereby more rapid infarct development. Therefore, the purpose was to evaluate the relationship between IQP and measures of myocardial injury in patients presenting with acute ST-elevation myocardial infarction (STEMI). METHODS: Seventy-seven patients with first-time STEMI were retrospectively included from the recently published SOCCER trial. All patients underwent a cardiac magnetic resonance (CMR) examination 2-6 days after the acute event. Infarct size (IS), myocardium at risk (MaR), and myocardial salvage index (MSI) were assessed and related to IQP. IQP measures assessed were; computer-generated QRS duration, QRS duration at maximum ST deviation, absolute IQP and relative IQP, all derived from a pre-PCI, 12-lead ECG. RESULTS: Median absolute IQP was 10 ms (range 0-115 ms). There were no statistically significant correlations between measures of IQP and any of the CMR measures of myocardial injury (absolute IQP vs IS, r = 0.03, p = 0.80; MaR, r = -0.01, p = 0.89; MSI, r = -0.05, p = 0.68). CONCLUSIONS: Unlike previous experimental studies, the IQP was limited in patients presenting at the emergency room with first-time STEMI and no correlation was found between IQP and CMR variables of myocardial injury in these patients. Therefore, IQP does not seem to be a suitable biomarker for triaging patients in this clinical context.

Junctional ST-depression and tall symmetrical T-waves with an obtuse marginal artery occlusion: A case report.

A 54-year-old man presented to the emergency department with chest pain and electrocardiogram (ECG) changes of acute ST-segment elevation myocardial infarction (STEMI) and junctional ST-depression with tall symmetrical T-waves (de Winter T-wave) in the lateral and inferior leads. Emergent coronary angiography revealed a culprit lesion in the gigantic obtuse marginal artery (OM). This case demonstrates the de Winter T-wave can occur in a patient with an acute occlusion of OM. Emergency physicians, ambulance staff, cardiologists and all involved in STEMI networks should familiarize themselves with this unusual ECG pattern and consider transferring patients for urgent angiography and reperfusion therapy.

Electrocardiographic findings of acute total occlusion associated with a sub-occlusion involving the left anterior descending and the right coronary artery.

BACKGROUND: The ECG characteristics of simultaneous acute occlusion/sub-occlusion of two coronary arteries involving the left anterior descending (LAD) and right (RCA) coronary artery have been rarely described in the literature. METHODS: We present two patient cases, where one of the arteries was totally occluded and the other one had a sub-occlusion with severely limited flow to demonstrate the ECG characteristics of this severe presentation of acute coronary syndrome. RESULTS: Two ECG patterns suggested simultaneous occlusions of the RCA and LAD. One pattern was ST-segment elevation (STE) in lead III higher than in lead II with concomitant STE in leads V3-V4. The other pattern was STE in lead III higher than in lead II with the concomitant Dressler - de Winter ECG pattern in leads V2-V4. CONCLUSIONS: We present two ECG presentations of simultaneous RCA and LAD occlusion/sub-occlusion. We consider these ECG features as high-risk markers in acute ST-elevation myocardial infarction.

In silico evaluation of the acute occlusion effect of coronary artery on cardiac electrophysiology and the body surface potential map.

Body surface potential map, an electric potential distribution on the body torso surface, enables us to infer the electrical activities of the heart. Therefore, observing electric potential projected to the torso surface can be highly useful for diagnosing heart diseases such as coronary occlusion. The BSPM for the heart of a patient show a higher level of sensitivity than 12-lead ECG. Relevant research has been mostly based on clinical statistics obtained from patients, and, therefore, a simulation for a variety of pathological phenomena of the heart is required. In this study, by using computer simulation, a body surface potential map was implemented according to various occlusion locations (distal, mid, proximal occlusion) in the left anterior descending coronary artery. Electrophysiological characteristics of the body surface during the ST segment period were observed and analyzed based on an ST isointegral map. We developed an integrated system that takes into account the cellular to organ levels, and performed simulation regarding the electrophysiological phenomena of the heart that occur during the first 5 minutes (stage 1) and 10 minutes (stage 2) after commencement of coronary occlusion. Subsequently, we calculated the bipolar angle and amplitude of the ST isointegral map, and observed the correlation between the relevant characteristics and the location of coronary occlusion. In the result, in the ventricle model during the stage 1, a wider area of ischemia led to counterclockwise rotation of the bipolar angle; and, during the stage 2, the amplitude increased when the ischemia area exceeded a certain size.

Recognising the de Winter ECG pattern - A time critical electrocardiographic diagnosis in the Emergency Department.

The de Winter ECG pattern is associated with proximal left anterior descending artery occlusion, being a significant risk factor for anterior wall ST elevation myocardial infarction. We present a case of a patient who attended our Emergency Department with chest pain and a prehospital ECG demonstrating transient infero-lateral lead ST segment elevation, which changed to the de Winter ECG pattern in our Emergency Department. She subsequently underwent primary PCI of the culprit lesion within the left anterior descending artery (LAD). Recognition of de Winter ECG pattern in the Emergency Department results in a time critical diagnosis for acute coronary occlusion and should be followed by emergency coronary revascularization.

Catheter Ablation in the Right Ventricular Outflow Tract Associated With Occlusion of Left Anterior Descending Coronary Artery.

Major vessel injury during right ventricular outflow tract ablation is not something widely recognized, and routine evaluation of the left anterior descending (LAD) artery location in relation to the septal right ventricle is not routinely performed. In the present article, we report a case of acute LAD occlusion after right ventricular outflow tract ablation and then illustrate the intimately close relationship of the LAD artery to the anterior septal site of the RVOT (approximately 2-3 cm under the pulmonic valve), using a combination of intracardiac echocardiography and 3-dimensional electroanatomical mapping recorded during a second case, in order to specifically point to the area at risk.

The Olson method for detection of acute myocardial ischemia in patients with coronary occlusion.

An automated ECG-based method may provide diagnostic support in the management of patients with acute coronary syndrome. The Olson method has previously proved to accurately identify the culprit artery in patients with acute coronary occlusion. METHODS: The Olson method was applied to 360 patients without acute myocardial ischemia and 52 patients with acute coronary occlusion. RESULTS: This study establishes the normal variation of the Olson wall scores in patients without acute myocardial ischemia, which provides the basis for implementation of the Olson method for triage of patients with acute coronary syndrome. All patients with acute occlusion had Olson wall scores above the upper limit of normal. CONCLUSION: The Olson method can be used for ischemia detection with very high sensitivity. Future studies are needed to explore specificity in patients with non-ischemic ST elevation.

Acute coronary occlusion and percutaneous coronary intervention after out-of-hospital cardiac arrest.

OBJECTIVES: Early coronary angiography (CAG) has been recommended in selected patients following out-of-hospital-cardiac-arrest (OHCA). We aimed to identify clinical features associated with acute coronary occlusion (ACO) and evaluate the associations between ACO, successful percutaneous coronary intervention (PCI) and outcomes in this population. METHODS: We included comatose OHCA patients treated with targeted temperature management (TTM) between December 2005 and September 2016 who underwent early CAG within 24 hours. The co-primary outcomes were all-cause 30-day mortality and good neurological outcome (modified Rankin Score [mRS] ≤2) at hospital discharge. RESULTS: Among 155 patients (93% shockable arrest rhythm, 55% with ST elevation), 133 (86%) had coronary artery stenosis ≥50% and 65 (42%) had ACO. ST elevation (sensitivity 74%, specificity 59%, OR 4.0, 95% CI 2.0-8.1) and elevated first troponin (sensitivity 88%, specificity 26%, OR 2.5, 95% CI 1.1-6.1) had limited sensitivity and specificity for ACO. Unadjusted 30-day mortality did not differ significantly by coronary disease severity or ACO. Successful PCI was associated with a lower risk of 30-day mortality (adjusted HR 0.5, 95% CI 0.2-0.9, P=.03), especially among patients with ACO (adjusted HR 0.4, 95% CI 0.1-0.9, P=0.03). After adjustment, ACO and PCI were not associated with the probability of good neurological outcome. CONCLUSIONS: In this select cohort of resuscitated OHCA patients undergoing CAG, unstable coronary disease is highly prevalent and successful PCI was associated with a higher probability of 30-day survival, especially among those with ACO. Neither ACO nor successful PCI were independently associated with good neurological outcome.

Preclinical identification of acute coronary syndrome without high sensitivity troponin assays using machine learning algorithms.

Preclinical management of patients with acute chest pain and their identification as candidates for urgent coronary revascularization without the use of high sensitivity troponin essays remains a critical challenge in emergency medicine. We enrolled 2760 patients (average age 70 years, 58.6% male) with chest pain and suspected ACS, who were admitted to the Emergency Department of the University Hospital Tübingen, Germany, between August 2016 and October 2020. Using 26 features, eight Machine learning models (non-deep learning models) were trained with data from the preclinical rescue protocol and compared to the "TropOut" score (a modified version of the "preHEART" score which consists of history, ECG, age and cardiac risk but without troponin analysis) to predict major adverse cardiac event (MACE) and acute coronary artery occlusion (ACAO). In our study population MACE occurred in 823 (29.8%) patients and ACAO occurred in 480 patients (17.4%). Interestingly, we found that all machine learning models outperformed the "TropOut" score. The VC and the LR models showed the highest area under the receiver operating characteristic (AUROC) for predicting MACE (AUROC = 0.78) and the VC showed the highest AUROC for predicting ACAO (AUROC = 0.81). A SHapley Additive exPlanations (SHAP) analyses based on the XGB model showed that presence of ST-elevations in the electrocardiogram (ECG) were the most important features to predict both endpoints.

Comparison of diagnostic accuracy of current left bundle branch block and ventricular pacing ECG criteria for detection of occlusion myocardial infarction.

BACKGROUND: Electrocardiographic detection of patients with occlusion myocardial infarction (OMI) can be difficult in patients with left bundle branch block (LBBB) or ventricular paced rhythm (VPR) and several ECG criteria for the detection of OMI in LBBB/VPR exist. Most recently, the Barcelona criteria, which includes concordant ST deviation and discordant ST deviation in leads with low R/S amplitudes, showed superior diagnostic accuracy but has not been validated externally. We aimed to describe the diagnostic accuracy of four available ECG criteria for OMI detection in patients with LBBB/VPR at the emergency department. METHODS: The unweighted Sgarbossa criteria, the modified Sgarbossa criteria (MSC), the Barcelona criteria and the Selvester criteria were applied to chest pain patients with LBBB or VPR in a prospectively acquired database from five emergency departments. RESULTS: In total, 623 patients were included, among which 441 (71%) had LBBB and 182 (29%) had VPR. Among these, 82 (13%) patients were diagnosed with AMI, and an OMI was identified in 15 (2.4%) cases. Sensitivity/specificity of the original unweighted Sgarbossa criteria were 26.7/86.2%, for MSC 60.0/86.0%, for Barcelona criteria 53.3/82.2%, and for Selvester criteria 46.7/88.3%. In this setting with low prevalence of OMI, positive predictive values were low (Sgarbossa: 4.6%; MSC: 9.4%; Barcelona criteria: 6.9%; Selvester criteria: 9.0%) and negative predictive values were high (all >98.0%). CONCLUSIONS: Our results suggests that ECG criteria alone are insufficient in predicting presence of OMI in an ED setting with low prevalence of OMI, and the search for better rapid diagnostic instruments in this setting should continue.

Acute left main coronary occlusion after transcatheter aortic valve implantation: life-saving intervention using the snare technique-a case report.

Background: Transcatheter aortic valve implantation (TAVI) has rapidly evolved and changed the field of structural cardiovascular intervention. Its advances lead to a marked reduction in the risk of complications and improved outcomes. However, TAVI is still associated with potential serious complications. Case summary: A 73-year-old man with severe aortic stenosis underwent TAVI using a 34-mm self-expanding aortic bioprosthesis. After valve deployment, the patient rapidly progressed to cardiac arrest. Acute left main occlusion, due to high valve implantation, was promptly recognized and advanced life support immediately initiated. Concomitantly, the valve was successfully retrieved toward the ascending aorta using the snare technique, resulting in immediate restoration of flow and successful cardiopulmonary resuscitation. Subsequently, a 29-mm balloon-expandable aortic bioprosthesis was uneventfully implanted. After TAVI, the patient had a remarkable clinical evolution and was discharged home at hospitalization day five without relevant electrocardiographic nor echocardiographic disturbances. At six-month follow-up, the patient remains asymptomatic and transthoracic echocardiography revealed a normofunctional aortic bioprosthesis with preserved left ventricular ejection fraction. Discussion: Acute coronary occlusion is a rare and life-threating complication of TAVI that may be prevented with accurate procedure planning. Pre-procedural computed tomography angiography is essential for a comprehensive patient evaluation, allowing appropriate valve selection, a key factor for successful management. Self-expandable valve retrieval with snare technique can be an appropriate strategy for the management of this complication. This case highlights the importance of performing these procedures in highly experienced centres and with fully equipped catheterization laboratories to allow timely interventions when facing unexpected events.

[Acute myocardial infarction in a young woman with systemic lupus erythematosus]. / Infarto agudo de miocardio en mujer joven con diagnóstico de lupus eritematoso sistémico.

We repor a case of acute ST elevation myocardial infarction in a 22-year-old patient with SLE, hypertension and nephropathy who underwent successful coronary angioplasty to a middle third of the left anterior descending artery. She evolved without signs of heart failure however, due to the delay in diagnosis, she presented severe deterioration of ventricular function. ST segment elevation myocardial infarction is a very rare event in young premenopausal women, but compared to the general population, patients with lupus have at least a 50% higher risk of suffering it regardless their age. In this population, the most frequent causes are vasculitis, early atherosclerosis and secondary thrombosis to antiphospholipid syndrome. In the context of lupus, conditions such as the presence of nephritis have been described as favoring the appearance of myocardial infarction, constituting subgroups of higher risk. The increased risk of AMI in patients with SLE must be taken into account and must be suspected as a differential diagnosis of precordial pain in young women, even those under 25 years of age, a population categorized as having low CV risk according to traditional scores. This would avoid delays in diagnosis and treatment with adverse consequences such as extensive myocardial necrosis and its impact on ventricular systolic function, as occurred in this patient.

Se presenta un caso de infarto agudo de miocardio con elevación del segmento ST en una paciente de 22 años de edad, con LES, HTA y nefropatía a la cual se le realizó angioplastia coronaria exitosa a tercio medio de arteria descendente anterior. Evolucionó sin signos de insuficiencia cardiaca, sin embargo, debido al retraso en el diagnóstico presentó deterioro grave de la función ventricular. El infarto agudo de miocardio con elevación del ST es un evento muy poco frecuente en mujeres pre menopáusicas pero, en comparación con la población general las pacientes con lupus eritematoso sistémico presentan al menos un 50% más de riesgo de padecerlo independientemente de la edad. En esta población, las etiologías más frecuentes son la vasculitis, la aterosclerosis precoz y la trombosis secundaria a síndrome antifosfolipídico. A su vez, en contexto de lupus, se han descripto condiciones como la presencia de nefritis lúpica, que favorecen aún más a la aparición del infarto de miocardio, constituyendo subgrupos de mayor riesgo. El incremento del riesgo de IAM en los pacientes con LES debe tenerse en cuenta y hay que sospechar como diagnóstico diferencial del dolor precordial aún en mujeres jóvenes, incluso menores de 25 años, población categorizada como de bajo riesgo cardiovascular según los scores y criterios tradicionales. Esto evitaría las demoras en el diagnóstico y tratamiento con consecuencias pronósticas adversas como la necrosis miocárdica extensa y su impacto negativo sobre la función sistólica ventricular como ocurrió en esta paciente.

Advances in the treatment of ST Elevation Myocardial Infarction in the UK.

The treatment of acute coronary occlusion with Primary PCI has been a major factor in improving outcomes of patients suffering STEMI in the last 15 years, and is the standard treatment for patients suffering STEMI in the UK. Treatment is beneficial for patients presenting within 12 hours of the onset of symptoms, with the goal being opening of the occluded artery within 150 min of the call for help. Opening of the occluded artery is typically completed with a drug-eluting stent followed by administration of antiplatelet medications for 12 months. Procedures are performed using the radial artery which is associated with improved outcomes compared to vascular access via the femoral artery. Evidence is growing to support full revascularisation including the treatment of severe narrowing in other blood vessels as well as the culprit vessel.

Diagnostic Accuracy Of The Electrocardiographic Decision Support - Myocardial Ischaemia (EDS-MI) Algorithm In Detection Of Acute Coronary Occlusion.

Electrocardiographic Decision Support - Myocardial Ischaemia (EDS-MI) is a graphical decision support for detection and localization of acute transmural ischaemia. A recent study indicated that EDS-MI performs well for detection of acute transmural ischaemia. However, its performance has not been tested in patients with non-ischaemic ST-deviation. We aimed to optimize the diagnostic accuracy of EDS-MI in patients with verified acute coronary occlusion as well as patients with non-ischaemic ST deviation and compare its performance with STEMI criteria. We studied 135 patients with non-ischaemic ST deviation (perimyocarditis, left ventricular hypertrophy, takotsubo cardiomyopathy and early repolarization) and 117 patients with acute coronary occlusion. In 63 ischaemic patients, the extent and location of the ischaemic area (myocardium at risk) was assessed by both cardiovascular magnetic resonance imaging and EDS-MI. Sensitivity and specificity of ST elevation myocardial infarction criteria were 85% (95% confidence interval (CI) 77, 90) and 44% (95% CI 36, 53) respectively. Using EDS-MI, sensitivity and specificity increased to 92% (95% CI 85, 95) and 81% (95% CI 74, 87) respectively (p=0.035 and p<0.001). Agreement was strong (83%) between cardiovascular magnetic resonance imaging and EDS-MI in localization of ischaemia. Mean myocardium at risk was 32% (± 10) by cardiovascular magnetic resonance imaging and 33% (± 11) by EDS-MI when the estimated infarcted area according to Selvester QRS scoring was included in myocardium at risk estimation. In conclusion, EDS-MI increases diagnostic accuracy and may serve as an automatic decision support in the early management of patients with suspected acute coronary syndrome. The added clinical benefit in a non-selected clinical chest pain population needs to be assessed.

A de Winter electrocardiographic pattern caused by left main coronary artery occlusion: A case report.

A de Winter electrocardiographic (ECG) pattern comprising precordial junctional ST depression followed by tall, positive symmetrical T waves in leads V1/V2 to V4/V6 is often concomitant with ST elevation in lead aVR. This finding strongly suggests proximal left anterior descending coronary artery occlusion. We described a patient who had the de Winter ECG pattern in leads V2 to V4 by acute left main coronary artery (LMCA) occlusion. The ECG also showed maximal ST depression in leads V4 to V5 and inverted T waves in leads V5 to V6. This finding indicated a global subendocardial ischemia ECG pattern, which suggested LMCA or three-vessel disease. Early recognition of this ECG manifestation is important for averting a disastrous prognosis in acute LMCA occlusion because emergent coronary intervention may be life-saving.

DIagnostic accuracy oF electrocardiogram for acute coronary OCClUsion resuLTing in myocardial infarction (DIFOCCULT Study).

BACKGROUND: Although ST-segment elevation (STE) has been used synonymously with acute coronary occlusion (ACO), current STE criteria miss nearly one-third of ACO and result in a substantial amount of false catheterization laboratory activations. As many other electrocardiographic (ECG) findings can reliably indicate ACO, we sought whether a new ACO/non-ACO myocardial infarction (MI) paradigm would result in better identification of the patients who need acute reperfusion therapy. METHODS: A total of 3000 patients were enrolled in STEMI, non-STEMI and control groups. All ECGs were reviewed by two cardiologists, blinded to any outcomes, for the current STEMI criteria and other subtle signs. A combined ACO endpoint was composed of peak troponin level, troponin rise within the first 24 h and angiographic appearance. The dead or alive status was checked from hospital records and from the electronic national database. RESULTS: In non-STEMI group, 28.2% of the patients were re-classified by the ECG reviewers as having ACO. This subgroup had a higher frequency of ACO, myocardial damage, and both in-hospital and long-term mortality compared to non-STEMI group. A prospective ACOMI/non-ACOMI approach to the ECG had superior diagnostic accuracy compared to the STE/non-STEMI approach in the prediction of ACO and long-term mortality. In Cox-regression analysis early intervention in patients with non-ACO-predicting ECGs was associated with a higher long-term mortality. CONCLUSIONS: We believe that it is time for a new paradigm shift from the STEMI/non-STEMI to the ACOMI/non-ACOMI in the acute management of MI. (DIFOCCULT study; ClinicalTrials.gov number, NCT04022668.).

Improving the Diagnosis of Culprit Left Circumflex Occlusion With Acute Myocardial Infarction in Patients With a Nondiagnostic 12-Lead ECG at Presentation: A Retrospective Cohort Study.

Background Left circumflex culprit is often missed by the standard 12-lead ECG . Extended lead systems (body surface potential map [ BSPM ]) should improve the diagnosis of culprit left circumflex stenosis with myocardial infarction. Methods and Results Retrospective analysis of a hospital research registry (August 2000-August 2010) comprising consecutive patients with (1) ischemic-type chest pain at rest; (2) 12-lead ECG and 80-lead BSPM at first medical contact; and (3) cardiac troponin-T 12 hours after symptom onset and/or creatine kinase MB fraction, were undertaken. Enrolled in the cohort were patients with culprit left circumflex stenosis (thrombolysis in myocardial infarction flow grade 0/1) at angiography. Acute myocardial infarction AMI was defined as cardiac troponin-T ≥0.1 µg/L and/or creatine kinase MB fraction >2 upper limits of normal. Enrolled were 482 patients: 168 had exclusion criteria. Of the remaining 314 (age 64±11 years; 62% male), 254 (81%) had AMI : of these, 231 had BSPM STE -sensitivity 0.91, specificity 0.72, positive predictive value 0.93, negative predictive value 0.65, and c-statistic 0.803 for AMI ( P<0.001). Of those with BSPM STE and AMI (n=231), STE was most frequently detected in the posterior (n=111, 48%), lateral (n=53, 23%), inferior (n=39, 17%), and right ventricular (n=21, 9%) territories. Conclusions Among patients with 12-lead ECG non-ST-segment-elevation myocardial infarction and culprit left circumflex stenosis, initial BSPM identifies ST-segment elevation beyond the territory of the 12-lead ECG . Greater use of the BSPM may result in earlier identification of AMI , which may lead to more rapid reperfusion.

Acute left main stem coronary occlusion following transcatheter aortic valve replacement in a patient without recognized coronary obstruction risk factors: a case report.

BACKGROUND: Acute coronary obstruction following transcatheter aortic valve replacement (TAVR) is an uncommon but life-threatening event. CASE SUMMARY: A 78-year-old man developed acute left main obstruction following transfemoral TAVR with a balloon-expandable valve. Cardiac arrest ensued, requiring emergent peripheral cardiopulmonary bypass. Percutaneous coronary intervention (PCI) to the left main coronary artery was performed with one drug-eluting stent. Intravascular ultrasound (IVUS) demonstrated focal underexpansion of the stent in its proximal segment which was not responsive to high-pressure non-compliant balloon dilatation, suggesting stent compression from either valve strut or calcific native leaflet. Therefore, to increase radial strength of the scaffolding at the site of compression, we deployed a second stent within the first stent, and further expanded that segment with high-pressure balloon inflations. Final IVUS demonstrated better expansion of the focally compressed segment. Following PCI, left ventricular function normalized completely. The patient was discharged from hospital on Day 3 post-procedure. At 12 weeks follow-up, his dyspnoea had improved significantly, and follow-up transthoracic echocardiography demonstrated normal left ventricular systolic function and normal aortic valve function. DISCUSSION: Established risk factors for coronary ostial occlusion include a short distance between the aortic annulus and the coronary ostia (<10 mm) and a narrow aortic root (<28 mm at the sinuses of Valsalva). These two factors increase the likelihood that the native valve leaflets are displaced over and obstruct the coronary ostia when the aortic bioprosthesis is deployed. Perplexingly, our patient did not present with any of the recognized risk factors for acute coronary occlusion, suggesting other factors might be at play. We suggest that a leaflet length to coronary sinus height ratio greater than 1 might be an additional useful predictor of coronary occlusion during TAVR. In addition, we suggest that if residual focal stent compression from either valve strut or calcific leaflet exists after stent deployment and the latter is resistant to balloon dilatation, deploying a second concentric layer of stent might improve the radial strength of the scaffolding and improve overall stent expansion.