The pathophysiology of patent foramen ovale and its related complications.

The foramen ovale plays a vital role in sustaining life in-utero; however, a patent foramen ovale (PFO) after birth has been associated with pathologic sequelae in the systemic circulation including stroke/transient ischemic attack (TIA), migraine, high altitude pulmonary edema, decompression illness, platypnea-orthodeoxia syndrome (POS) and worsened severity of obstructive sleep apnea. Importantly, each of these conditions is most commonly observed among specific age groups: migraine in the 20 to 40s, stroke/TIA in the 30-50s and POS in patients >50 years of age. The common and central pathophysiologic mechanism in each of these conditions is PFO-mediated shunting of blood and its contents from the right to the left atrium. PFO-associated pathologies can therefore be divided into (1) paradoxical systemic embolization and (2) right to left shunting (RLS) of blood through the PFO. Missing in the extensive literature on these clinical syndromes are mechanistic explanations for the occurrence of RLS, including timing and the volume of blood shunted, the impact of age on RLS, and the specific anatomical pathway that blood takes from the venous system to the left atrium. Visualization of the flow pattern graphically illustrates the underlying RLS and provides a greater understanding of the critical flow dynamics that determine the frequency, volume, and pathway of flow. In the present review, we describe the important role of foramen ovale in in-utero physiology, flow visualization in patients with PFO, as well as contributing factors that work in concert with PFO to result in the diverse pathophysiological sequelae.

Impact of biological sex on valvular heart disease, interventions, and outcomes.

Valvular heart disease (VHD) is common, affecting >14% of individuals aged >75, and is associated with morbidity, including heart failure and arrhythmia, and risk of early mortality. Increasingly, important sex differences are being found between males and females with VHD. These sex differences can involve the epidemiology, pathophysiology, presentation, diagnosis, and outcomes of the disease. Females are often disadvantaged, and female sex has been shown to be associated with delayed diagnosis and inferior outcomes in various forms of VHD. In addition, the unique pathophysiologic state of pregnancy is associated with increased risk for maternal and fetal morbidity and mortality in many forms of VHD. Therefore, understanding and recognizing these sex differences, and familiarity with the attendant risks of pregnancy and management of pregnant females with VHD, is of great importance for any primary care or cardiovascular medicine practitioner caring for the female patient. This review will outline sex differences in aortic, mitral, pulmonic, and tricuspid VHD, with particular focus on differences in pathophysiology, clinical presentation, and outcomes. In addition, the pathophysiology and management implications of pregnancy will be discussed.

Acute kidney injury after radial or femoral artery access in ST-segment elevation myocardial infarction: AKI-SAFARI.

BACKGROUND: Acute kidney injury (AKI) complicating primary percutaneous coronary intervention (PCI) is an independent predictor of short- and long-term outcomes in patients presenting with ST-elevation myocardial infarction (STEMI). Prior studies suggest a lower incidence of AKI in patients undergoing PCI through radial artery compared to femoral artery access; however, no randomized clinical trials have specifically investigated this question in patients presenting with STEMI. METHODS: To determine whether radial access (RA) is associated with a reduced frequency of AKI following primary PCI, we performed a substudy of the SAFARI-STEMI trial. The SAFARI-STEMI trial was an open-label, multicenter trial, which randomized patients presenting with STEMI to RA or femoral access (FA), between July 2011 and December 2018. The primary outcome of this post hoc analysis was the incidence of AKI, defined as an absolute (>0.5 mg/dL) or relative (>25%) increase in serum creatinine from baseline. RESULTS: In total 2,285 (99.3%) of the patients enrolled in SAFARI-STEMI were included in the analysis-1,132 RA and 1,153 FA. AKI occurred in 243 (21.5%) RA patients and 226 (19.6%) FA patients (RR: 0.91, 95% CI: 0.78-1.07, P = .27). An absolute increase in serum creatinine >0.5 mg/dL was seen in 49 (4.3%) radial and 52 (4.5%) femoral patients (RR: 1.04, 95% CI: 0.71-1.53, P = .83). AKI was lower in both groups when the KDIGO definition was applied (RA 11.9% vs FA 10.8%; RR: 0.90, 95% CI: 0.72-1.13, P = .38). CONCLUSIONS: Among STEMI patients enrolled in the SAFARI-STEMI trial, there was no association between catheterization access site and AKI, irrespective of the definition applied. These results challenge the independent association between catheterization access site and AKI noted in prior investigations.

Incidence, predictors, and clinical outcomes of coronary obstruction following transcatheter aortic valve replacement for degenerative bioprosthetic surgical valves: insights from the VIVID registry.

Aims: There are limited data on coronary obstruction following transcatheter valve-in-valve (ViV) implantation inside failed aortic bioprostheses. The objectives of this study were to determine the incidence, predictors, and clinical outcomes of coronary obstruction in transcatheter ViV procedures. Methods and results: A total of 1612 aortic procedures from the Valve-in-Valve International Data (VIVID) Registry were evaluated. Data were subject to centralized blinded corelab computed tomography (CT) analysis in a subset of patients. The virtual transcatheter valve to coronary ostium distance (VTC) was determined. A total of 37 patients (2.3%) had clinically evident coronary obstruction. Baseline clinical characteristics in the coronary obstruction patients were similar to controls. Coronary obstruction was more common in stented bioprostheses with externally mounted leaflets or stentless bioprostheses than in stented with internally mounted leaflets bioprostheses (6.1% vs. 3.7% vs. 0.8%, respectively; P < 0.001). CT measurements were obtained in 20 (54%) and 90 (5.4%) of patients with and without coronary obstruction, respectively. VTC distance was shorter in coronary obstruction patients in relation to controls (3.24 ± 2.22 vs. 6.30 ± 2.34, respectively; P < 0.001). Using multivariable analysis, the use of a stentless or stented bioprosthesis with externally mounted leaflets [odds ratio (OR): 7.67; 95% confidence interval (CI): 3.14-18.7; P < 0.001] associated with coronary obstruction for the global population. In a second model with CT data, a shorter VTC distance predicted this complication (OR: 0.22 per 1 mm increase; 95% CI: 0.09-0.51; P < 0.001), with an optimal cut-off level of 4 mm (area under the curve: 0.943; P < 0.001). Coronary obstruction was associated with a high 30-day mortality (52.9% vs. 3.9% in the controls, respectively; P < 0.001). Conclusion: Coronary obstruction following aortic ViV procedures is a life-threatening complication that occurred more frequently in patients with prior stentless or stented bioprostheses with externally mounted leaflets and in those with a short VTC.

Physiologic significance of coronary collaterals in chronic total occlusions.

Chronic total occlusions (CTOs) are commonly found in patients with coronary artery disease, and a system of collateral connections are found in almost all of these patients. These collateral vessels serve to prevent myocardial necrosis but are not sufficient to prevent myocardial ischemia during exercise. Unfortunately, the presence of well-developed collaterals has been used as argument against CTO revascularization. Many continue to falsely believe that these patients are "protected" by collaterals and, therefore, CTO recanalization is not indicated. Our knowledge of the physiologic significance of coronary collaterals has increased significantly over the past several years. Studies utilizing coronary pressure and flow velocity have answered a number of basic physiologic questions. We therefore sought to review the evidence for coronary collateral flow and their clinical significance in patients with CTOs.

Permanent Pacemaker-Mediated Exertional Hypoxemia in a Patient With Ebstein Anomaly.

Patients with Ebstein anomaly are known to have a higher incidence of interatrial communications and shunting of blood and its components through, mainly due to either streaming of tricuspid regurgitation or due to elevated right atrial pressure. Here we describe a case where permanent pacemaker lead kept a patent foramen ovale open leading to right-to-left shunting of blood and exertional hypoxemia. This is the first such case report in the published literature.

Correlation of Impedance Cardiography-Derived and Cardiac Magnetic Resonance-Derived Stroke Volumes.

Cardiac output (CO) and other hemodynamic parameter measurements play an important role in the management of cardiovascular conditions; however, due to limitations of current day technologies, such measurements are either not routinely performed or incorporated into clinical practice. Moreover, measurement of these hemodynamic parameters in the outpatient setting at different time points to assess interval change is currently not feasible. We attempted to validate total-body impedance cardiography-based Non-Invasive Cardiac System (NICaS) derived stroke volume (SV) with that from cardiac magnetic resonance (CMR), a current day gold standard method of assessment. We compared SV, as it is the primary unit of measurement utilized by both technologies. Forty-one consecutive patients undergoing CMR were also investigated by NICaS following CMR. The consistency of non-invasive technology-derived SV measurement was validated by NICaS measurement in 10 subjects, both before and after CMR. Of the 41 enrolled patients; data from 38 patients was adequate for comparison (motion artifact prevented CMR measures in 3 patients). Fourteen patients (37%) were female; mean age was 55 ± 15 years (28-87 years) and body-mass index was 28.7 ± 5.5 kg/m2 (20.5-41.9 kg/m2). Hypertrophic cardiomyopathy (9/41) was the most common study indication for CMR. NICaS-derived SV strongly correlated with CMR [NICaS 77 ± 20 ml (31-123 ml) and CMR 84 ± 23 ml (47-132 ml); P < 0.001; r = 0.77; ICC = 0.73]. The Bland-Altman limits of agreement between NICaS and CMR were -26.7% and 39.9%. NICaS-derived SV collected before and after MRI did not differ [80 ± 18 ml (51-102 ml) pre and 76 ± 17 ml (50-99 ml) post; P = 0.0007, Kappa = 1]. Agreement between NICaS-derived and CMR-derived SV was within the acceptable range of boundaries set by the US Food and the Drug Administration. Consistency in SV measurement at different time-points may allow use of this technology to identify interval hemodynamic changes noninvasively.

The Canadian WATCHMAN Registry for Percutaneous Left Atrial Appendage Closure.

Background: Access to left atrial appendage closure (LAAC) in Canada is limited, due to funding restrictions. This work aimed to assess Canadian clinical practice on patient selection, postprocedural antithrombotic therapy, and safety and/or efficacy with WATCHMAN device implantation. Methods: Seven Canadian centres implanting the WATCHMAN device participated in this prospective multicentre, observational registry. All procedures were done under general anesthesia with transesophageal echocardiography guidance. Patients were prospectively followed for 2years. The long-term stroke rate was compared with the expected rate based on the CHA2DS2-VASc score. Results: A total of 272 patients who underwent LAAC with the WATCHMAN device between December 2013 and August 2019 (mean age: 75.4 years [standard deviation {SD}: 8.75]; male, 63.2%; CHA2DS2-VASc score: 4.35 [SD: 1.64]; HAS-BLED score: 3.55 [SD: 0.94]) were included. Most patients (90.4%) had prior history of bleeding (major, 80.5%; minor, 21.7%). The WATCHMAN device was successfully implanted in 269 patients (98.9%), with a few procedure-related complications, including 5 pericardial effusions requiring drainage (1.8%), and 1 death (0.4%; 22 days post-LAAC from respiratory failure). Post-LAAC antithrombotic therapy included dual antiplatelet therapy in 70.6%, single antiplatelet therapy in 18.4%, and oral anticoagulation in 13.6%. During the follow-up period (mean: 709.7 days [SD: 467.2]), an 81.4% reduction of the ischemic stroke rate occurred, based on the expected rate from the CHA2DS2-VASc score (6.0% expected vs 1.1% observed). Device-related thrombus was detected in 1.8%. Conclusions: The majority of Canadian patients who underwent LAAC had oral anticoagulation contraindication due to prior bleeding, and most were safely treated with antiplatelet therapy post-LAAC, with a low device-related thrombus incidence. Long-term follow-up demonstrated that LAAC achieved a significant reduction in ischemic stroke rate.

Contexte: Au Canada, l'accès à la fermeture de l'appendice auriculaire gauche (FAAG) est limité en raison de restrictions quant au financement de cette intervention. Le présent rapport visait à évaluer les pratiques cliniques canadiennes sur la sélection des patients, le traitement antithrombotique après l'intervention et l'innocuité ou l'efficacité par l'implantation d'un dispositif WATCHMAN. Méthodologie: Sept centres canadiens procédant à l'implantation du dispositif WATCHMAN ont participé à ce registre observationnel, prospectif et multicentrique. Toutes les interventions ont été réalisées sous anesthésie générale avec guidage par échocardiographie transœsophagienne. Les patients ont par la suite été suivis de manière prospective pendant deux ans. Le taux d'AVC à long terme a été comparé au taux attendu, selon le score CHA2DS2-VASc. Résultats: Ont été inclus à l'étude 272 patients ayant subi une FAAG avec implantation d'un dispositif WATCHMAN entre décembre 2013 et août 2019 (âge moyen : 75,4 ans [écart-type {É.-T.} : 8,75]; hommes : 63,2 %; score CHA2DS2-VASc : 4,35 [É.-T. : 1,64]; score HAS-BLED : 3,55 [É.-T. : 0,94]). La plupart des patients (90,4 %) avaient des antécédents de saignements (majeurs : 80,5 %; mineurs : 21,7 %). Le dispositif WATCHMAN a bien été implanté chez 269 patients (98,9 %), avec quelques complications associées à l'intervention, dont cinq effusions péricardiques nécessitant un drainage (1,8 %) et un décès (0,4 %; 22 jours après la FAAG, en raison d'une insuffisance respiratoire). Le traitement antithrombotique après la FAAG comprenait une bithérapie antiplaquettaire dans 70,6 % des cas, une monothérapie antiplaquettaire dans 18,4 % des cas et une anticoagulothérapie orale dans 13,6 % des cas. Pendant la période de suivi (durée moyenne : 709,7 jours [É.-T. : 467,2]), on a noté une réduction de 81,4 % du taux d'AVC ischémique observé par rapport au taux attendu selon le score CHA2DS2-VASc (taux attendu : 6,0 %; taux observé : 1,1 %). Un thrombus associé au dispositif a été détecté dans 1,8 % des cas. Conclusions: La majorité des patients canadiens qui ont subi une FAAG présentaient des contre-indications à l'anticoagulothérapie orale en raison de leurs antécédents de saignements, et la plupart ont été traités de manière sécuritaire par des thérapies antiplaquettaires après la chirurgie, avec un faible taux d'incidence de thrombus associé au dispositif. Le suivi à long terme a montré que la FAAG permet d'obtenir une réduction importante du taux d'AVC ischémique.

Chest Pain Evaluation: Diagnostic Testing.

Chest pain/discomfort (CP) is a common symptom and can be a diagnostic dilemma for many clinicians. The misdiagnosis of an acute or progressive chronic cardiac etiology may carry a significant risk of morbidity and mortality. This review summarizes the different options and modalities for establishing the diagnosis and severity of coronary artery disease. An effective test selection algorithm should be individually tailored to each patient to maximize diagnostic accuracy in a timely fashion, determine short- and long-term prognosis, and permit implementation of evidence-based treatments in a cost-effective manner. Through collaboration, a decision algorithm was developed (www.chowmd.ca/cadtesting) that could be adopted widely into clinical practice.

La douleur ou la gêne thoracique sont des symptômes fréquents qui peuvent poser un dilemme diagnostique pour de nombreux médecins. Les erreurs de diagnostic d'une cause aiguë ou chronique progressive d'origine cardiaque peuvent d'ailleurs entraîner un risque considérable de morbidité et de mortalité. La présente synthèse porte sur les différentes options et modalités d'établissement du diagnostic et de la gravité d'une coronaropathie. Un algorithme efficace pour le choix des tests doit être adapté à chaque patient afin de maximiser l'exactitude diagnostique dans les plus brefs délais, de déterminer le pronostic à court et à long terme, et de permettre une mise en œuvre de traitements fondés sur des données probantes tout en tenant compte des coûts. Un algorithme décisionnel a donc été conjointement mis au point (www.chowmd.ca/cadtesting) et pourrait être largement adopté dans la pratique clinique.

The acutely occluded left main coronary artery culprit in cardiogenic shock and initial percutaneous coronary intervention: a substudy of the Manitoba "no option" left main PCI registry.

We aim to describe the in-hospital outcomes of the first reported Canadian cohort of patients with cardiogenic shock and acute myocardial infarction (MI) due to acute and total occlusion of the left main coronary artery, treated with initial percutaneous coronary intervention (PCI). Acute left main thromboses with cardiogenic shock were identified (N = 8) from a retrospective consecutive cohort of high risk left main PCI (N = 56) performed at our institution from 2004-2009. The mean age was 62.3 ± 13.2 years, with 6 (75%) male patients. Successful PCI was performed in all patients, with thrombectomy utilized in 4 patients (50%), stenting in 7 patients (88%), and intra-aortic balloon pump augmentation in 7 patients (88%). Two patients (25%) required extracorporeal membrane oxygenation (ECMO) and 2 other patients required ventricular assist devices. Post-PCI coronary artery bypass grafting (CABG) was performed for 2 patients (25%). The mean SYNTAX score was 26.6 ± 10.5. The mean logistic EuroSCORE was 30.4 ± 12.6%. In-hospital mortality occurred in 3 patients (38%). Acute left main occlusion is a rare but devastating presentation of myocardial infarction, invariably with cardiogenic shock. Emergent PCI may be an effective method to acutely revascularize this subset of patients; however, aggressive post-PCI care including ECMO, CABG, and ventricular support may be required to improve patient survival.

Validation of the Emory Risk Score in the Transcatheter Aortic Valve Implantation Population: A Canadian Perspective.

Background: Permanent pacemaker (PPM) implantation may be indicated post-transcatheter aortic valve implantation (TAVI). The Emory Risk Score (ERS) is a validated predictive risk score of the need for a PPM post-TAVI using a balloon-expandable valve. Our objectives were to determine the validity of the ERS in our local TAVI population with both balloon-expandable and self-expanding valves and to identify additional electrocardiographic (ECG) parameters predictive of the need for a PPM post-TAVI. Methods: Retrospective chart and electronic database reviews were performed to collect demographic and procedural information. Two expert readers reviewed all ECGs. Independent factors associated with PPM implantation were examined with multivariable logistic regression via a stepwise selection process with calculation of the area under the receiver operating characteristic curve to assess model discrimination. Results: The overall PPM implantation rate was 11.7%; rates were 9% for the Sapien 3 valves, 10% for the Evolut Pro valves, and 17% for the Evolut R valves. The ERS was found to not be predictive of need for PPM post-TAVI for the entire cohort. Right bundle branch block was the only ERS parameter independently associated with new PPM implant (8.5% vs 25%, odds ratio = 3.59, P = 0.01). No additional ECG parameters met the criteria for statistical significance. Conclusions: The poor predictive value of the ERS in determining the need for a PPM post-TAVI in our patient population suggests that further refinement of a formula (or risk-calculator) is warranted. Identification of a precise risk-calculator is likely to facilitate patient mobilization and reduce inpatient healthcare resource utilization.

Introduction: L'implantation d'un stimulateur cardiaque permanent (SCP) peut être indiquée après l'implantation valvulaire aortique par cathéter (post-IVAC). L'Emory Risk Score (ERS) est un score de prédiction du risque validé de la nécessité d'un SCP post-IVAC au moyen d'une valve expansible par ballonnet. Nous avions pour objectif de déterminer la validité de l'ERS auprès de notre population ayant eu une IVAC soit par valve expansible par ballonnet ou valve auto-expansible, et de déterminer d'autres paramètres électrocardiographiques (ECG) prédictifs de la nécessité d'un SCP post-IVAC. Méthodes: Nous avons réalisé des revues rétrospectives de dossiers et de bases de données électroniques pour collecter les données démographiques et interventionnelles. Deux experts ont lu et interprété tous les ECG. Les facteurs indépendants associés à l'implantation du SCP ont été examinés en effectuant la régression logistique multivariée par processus de sélection pas-à-pas au moyen du calcul de la surface sous la courbe caractéristique d'efficacité du récepteur afin d'évaluer la discrimination du modèle. Résultats: Le taux global d'implantation d'un SCP était de 11,7 % ; les taux étaient de 9 % pour les valves Sapien 3, de 10 % pour les valves Evolut Pro et de 17 % pour les valves Evolut R. Nous avons observé que l'ERS ne permettait pas de prédire si l'implantation d'un SCP post-IVAC était nécessaire pour la cohorte entière. Le bloc de branche droit était le seul paramètre de l'ERS indépendamment associé à la nouvelle implantation d'un SCP (8,5 % vs 25 %, rapport de cotes = 3,59, P = 0,01). Aucun autre paramètre ECG ne satisfaisait au critère de signification statistique. Conclusions: La faible valeur prédictive de l'ERS à déterminer la nécessité d'un SCP post-IVAC au sein de notre population de patients montre que des améliorations de la formule (ou calculateur de risques) sont justifiées. L'identification d'un calculateur de risques précis devrait favoriser l'adhésion des patients et réduire l'utilisation des ressources en soins de santé en milieu hospitalier.

Surgical Triage and Timing for Patients With Coronavirus Disease: A Guidance Statement from The Society of Thoracic Surgeons.

The coronavirus disease 2019 (COVID-19) pandemic continues to disrupt the provision of cardiac procedural services due to overwhelming interval surges in COVID-19 cases and the associated crisis of cardiac intervention deferment. Despite the availability of widespread testing, highly efficacious vaccines, and intensive public health efforts, the pandemic is entering its third year, where new severe acute respiratory syndrome-coronavirus-2 variants have increased the likelihood that patients scheduled for a cardiac intervention will contract COVID-19 in the perioperative period. The Society of Thoracic Surgeons (STS) Workforce on Critical Care, the STS Workforce on Adult Cardiac and Vascular Surgery, and the Canadian Society of Cardiac Surgeons have developed this document, endorsed by the STS and affirmed by the Society of Cardiovascular Angiography and Interventions and the Canadian Association of Interventional Cardiology, to provide guidance for cardiac procedure deferment and intervention timing for preoperative patients diagnosed with COVID-19. This document is intended for the perioperative cardiac surgical team and outlines the present state of the pandemic, the impact of COVID-19 on intervention outcome, and offers a recommended algorithm for individualized cardiac procedure triage and timing.

Rotational Atherectomy in the Management of Ruptured and Entrapped Coronary Angioplasty Balloon.

Retention and entrapment of angioplasty device fragments is a rare consequence of percutaneous coronary intervention (PCI). Due to advances in retrieval devices and introduction of new interventional techniques the need for emergency surgery has reduced significantly. There might also be clinical scenarios were remnants of retained fragments might have to be left within the coronary vessel and this might be the most appropriate option. Here we report a case of a ruptured non-compliant angioplasty balloon that was entrapped in the right coronary artery and retained in situ after multiple failed attempts at percutaneous retrieval. Medical therapy failed and hence rotation atherectomy had to be performed followed by stent implantation, there by jailing the retained fragments underneath the stent struts. To our knowledge this is the first description of rotational atherectomy of an entrapped balloon to allow for percutaneous revascularization.

Computed tomography coronary angiography for patients with heart failure (CTA-HF): a randomized controlled trial (IMAGE-HF 1C).

AIMS: This randomized controlled trial sought to determine the financial impact of an initial diagnostic strategy of coronary computed tomography angiography (CCTA) in patients with heart failure (HF) of unknown aetiology. Invasive coronary angiography (ICA) is used to investigate HF patients. CCTA may be a non-invasive cost-effective alternative to ICA. This randomized controlled trial sought to determine the financial impact of an initial diagnostic strategy of coronary computed tomography angiography (CCTA) in patients with heart failure (HF) of unknown aetiology. METHODS AND RESULTS: This multicentre, international trial enrolled patients with HF of unknown aetiology. The primary outcome was the cost of CCTA vs. ICA strategies at 12 months. Clinical outcomes were also collected. An 'intention-to-diagnose' analysis was performed and a secondary 'as-tested' analysis was based on the modality received. Two hundred and forty-six patients were randomized (age = 57.8 ± 11.0 years, ejection fraction = 30.1 ± 10.1%). The severity of coronary artery disease was similar in both groups. In the 121 CCTA patients, 93 avoided ICA. Rates of downstream ischaemia and viability testing were similar for both arms. There were no significant differences in the composite clinical outcomes or quality of life measures. The cost of CCTA trended lower than ICA [CDN -$871 (confidence interval, CI -$4116 to $3028)]. Using an 'as-tested' analysis, CCTA was associated with a decrease in healthcare costs (CDN -$2932, 95% CI -$6248 to $746). CONCLUSION: In patients with HF of unknown aetiology, costs were not statistically different between the CCTA and ICA strategies. CLINICAL TRIALS.GOV: NCT01283659.

Right and left ventricular uptake with Rb-82 PET myocardial perfusion imaging: markers of left main or 3 vessel disease.

BACKGROUND: Relative myocardial perfusion imaging may underestimate severity of coronary disease (CAD), particularly in cases of balanced ischemia. Can quantification of peak left (LV) and right (RV) ventricular Rb-82 uptake measurements identify patients with left main or 3 vessel disease? METHODS: Patients (N = 169) who underwent Rb-82 PET MPI and coronary angiography were categorized as having no significant coronary stenosis (n = 60), 1 or 2 vessel disease (n = 81), or left main disease/3 vessel disease (n = 28), based on angiography. Maximal LV and RV ventricular myocardial Rb-82 uptake was measured during stress and rest. RESULTS: Failure to augment LV uptake by >or= 8500 Bq/cc at stress, predicted left main or 3 vessel disease with a sensitivity of 93% and specificity of 61% (area under curve = 0.83). A >or=10% increase in RV: LV uptake ratios with stress over rest was 93% specific (area under curve = 0.74) for left main or 3 vessel disease. These indices incrementally predicted left main or 3 vessel disease compared to models including age, gender, cardiac risk factors, and summed stress and difference scores. CONCLUSION: Quantifying maximal rest and stress LV and RV uptake with PET myocardial perfusion imaging may independently and incrementally identify patients with left main or 3 vessel disease.

Zero-Contrast Intravascular Lithotripsy Angioplasty Facilitated by Intravascular Ultrasound.

A 49-year-old female with severe kidney dysfunction presented with an acute coronary syndrome. After angiography demonstrated severe disease in the left anterior descending and obtuse marginal arteries, she underwent staged percutaneous intervention with intravascular lithotripsy under fluoroscopic and intravascular ultrasound guidance with the use of zero contrast. She did well and went home 3 days post procedure with no deterioration in her renal function. This demonstrates the feasibility of complex coronary intervention with no contrast requirement.