Imaging for percutaneous left atrial appendage closure.

Percutaneous left atrial appendage (LAA) closure is increasingly performed worldwide as an alternative to long-term oral anticoagulation, especially for patients who are considered ineligible for anticoagulation. This is a complex procedure with success that hinges upon good understanding of the LAA and surrounding structures anatomy. Multimodality imaging can provide important three-dimensional appreciation of the LAA anatomy, which facilitates procedural safety and success. Thus, proceduralists and imagers involved with LAA closure should have good comprehension of such imaging modalities (cardiac CT angiography, transesophageal echocardiography, and/or intracardiac echocardiography) prior to embarking on this procedure. © 2016 Wiley Periodicals, Inc.

The prognostic importance of the diastolic pulmonary gradient, transpulmonary gradient, and pulmonary vascular resistance in patients undergoing transcatheter aortic valve replacement.

OBJECTIVES: To evaluate the association between markers of precapillary pulmonary hypertension (PH) and survival in transcatheter aortic valve replacement (TAVR). BACKGROUND: The importance of precapillary PH has been sparsely investigated in patients undergoing TAVR. It may prove an important risk factor for poor outcomes. METHODS: We identified patients at our institution undergoing TAVR with a baseline right heart catheterization (RHC) demonstrating PH. We evaluated the association between markers of precapillary PH and survival including the diastolic pulmonary gradient (DPG), transpulmonary gradient (TPG), and pulmonary vascular resistance (PVR). A multivariable analysis was performed using Cox Proportional Hazards Models, adjusting for age, gender, body mass index, and pulmonary artery systolic pressure (PASP) on echocardiography. RESULTS: We identified 133 patients with PH on RHC. Of these 111 had low DPG and 22 had high DPG. All 3 markers of precapillary PH were associated with worse survival post TAVR, with OR of 2.1 (95% CI 1.1-3.9, P = 0.02), 3.4 (95% CI 1.8-6.4, P < 0.001) and 2.5 (95% CI 1.4-4.5, P = 0.003) for high DPG, TPG, and PVR, respectively. On multivariable analysis, both TPG and PVR remained predictors of worse survival, with OR of 3.4 (95% CI 1.7-6.9, P = 0.001) and 2.5 (95% CI 1.4-4.5, P = 0.003). Echocardiographic PASP and DPG were not predictive of survival. CONCLUSIONS: In patients undergoing TAVR, parameters of precapillary PH are associated with lower survival, and provide incremental prognostication over echocardiographic PASP. RHC should continue to play an important role in risk stratification prior to TAVR. © 2017 Wiley Periodicals, Inc.

Comparing Measurements of CT Angiography, TEE, and Fluoroscopy of the Left Atrial Appendage for Percutaneous Closure.

BACKGROUND: Left atrial appendage (LAA) closure requires accurate preprocedural measurements, and trans-esophageal echocardiography (TEE), cardiac computed tomography angiography (CCTA) and fluoroscopy can be utilized. However, correlations between these measurements remain inadequately assessed. METHODS: Patients who underwent LAA closure at Vancouver General Hospital who had baseline LAA measurements by CCTA, TEE, and fluoroscopy were included in this analysis. CCTAs were performed with prospective-ECG-gating with Toshiba 320-detector or Siemens second generation 128-slice dual-source scanners, and images interpreted with VitreaWorkstation.™ LAA maximal dimensions were obtained for all patients at: (1) Amplatzer Cardiac Plug (ACP)/Amulet landing zone 10 mm within orifice, (2) WATCHMAN ostium, and (3) WATCHMAN depth measurements. Correlations and agreements were compared. RESULTS: We report 50 consecutive patients who underwent LAA closure (8 ACP, 10 Amulet, 32 WATCHMAN). Average age was 75.2 ± 8.7 years, mean CHADS2 score 3.0 ± 1.3, and CHA2 DS2 -VASc 4.7 ± 1.5. Procedural device implantation success was 100%. For ACP landing zone, mean maximal measurements were 24.1 ± 4.7 mm with CCTA, 22.3 ± 4.9 mm TEE, and 19.9 ± 5.6 mm fluoroscopy (P < 0.001); R value 0.81 fluoroscopy/CTA, 0.67 fluoroscopy/TEE, and 0.80 CTA/TEE. For WATCHMAN ostium, mean maximal measurements were 25.8 ± 4.7 mm CCTA (P < 0.001 vs. fluoroscopy, P = 0.16 vs. TEE), 25.1 ± 4.4 mm TEE (P = 0.016 vs. fluoroscopy), and 23.8 ± 4.9 mm fluoroscopy; R value 0.71 fluoroscopy/CTA, 0.65 fluoroscopy/TEE, and 0.74 CTA/TEE. Depth measurements were 34.3 ± 5.7 mm with CCTA, 31.1 ± 6.5 mm TEE, and 27.8 ± 7.1 mm fluoroscopy (all P < 0.01); and correlations with R value 0.28 fluoroscopy/CTA, 0.22 fluoroscopy/TEE, and 0.56 CTA/TEE. CONCLUSIONS: All 3 imaging modalities correlated with ACP landing zone and WATCHMAN ostium measurements, with CCTA providing the largest measurements, followed by TEE and fluoroscopy.

Instantaneous Decrease in Left Ventricular Afterload during Transcatheter Aortic Valve Implantation Results in Immediate Changes in Left Ventricular Strain.

Severe aortic stenosis causes chronic increased afterload on the left ventricle (LV) resulting in myocardial hypertrophy and ultimately dysfunction if left untreated. Transcatheter aortic valve implantation (TAVI) immediately decreases the afterload on the LV by reducing the pressure gradient through the aortic valve. In our study, we aim to evaluate immediate changes in LV mechanics using intra-procedural transesophageal echocardiography (TEE) to assess circumferential and radial strain via speckle tracking. Intra-operative TEE was performed during TAVI for 53 patients (mean age 84 ± 8 years). Two-dimensional images in the transgastric view were acquired at the level of the papillary muscle. Circumferential and radial strain was calculated using speckle tracking with Philips Qlab software. Global LV afterload was measured by calculating valvulo-arterial impedance (Zva). Immediately post-TAVI, there was a change in both radial strain rate (Pre: 0.73 ± 0.04 vs. Post: 0.88 ± 0.04 per second, P < 0.001) and circumferential strain rate (-0.53 ± 0.04 (pre) vs. -0.74 ± 0.04 (post) per second, P < 0.001). There was also an immediate improvement in circumferential global strain parameters (-14.5 ± 5% (pre) vs. -16.0 ± 4.7% (post), P < 0.05), whereas there was no significant change seen in global radial strain (15.6 ± 0.8% (pre) vs. 15.2 ± 0.9% (post), P = 0.69). No significant change was seen in LV ejection fraction (51.5 ± 14.2% (pre) vs. 52.1 ± 14.0% (post), P = 0.77). Speckle tracking using TEE images is feasible and identifies significant improvements in LV strain and strain rate immediately following TAVI that is not detected by conventional measure of LV function.

Pre-hospital heparin use for ST-elevation myocardial infarction is safe and improves angiographic outcomes.

AIMS: This study aims to evaluate if pre-hospital heparin administration by paramedics is safe and improves clinical outcomes. METHODS AND RESULTS: Using the multicentre Victorian Cardiac Outcomes Registry, linked with state-wide ambulance records, we identified consecutive patients undergoing primary percutaneous coronary intervention for STEMI between January 2014 and December 2018. Information on thrombolysis in myocardial infarction (TIMI) flow at angiography was available in a subset of cases. Patients receiving pre-hospital heparin were compared to those who did not receive heparin. Findings at coronary angiography and 30-day clinical outcomes were compared between groups. Propensity-score matching was performed for risk adjustment. We identified a total of 4720 patients. Of these, 1967 patients had TIMI flow data available. Propensity-score matching in the entire cohort yielded 1373 matched pairs. In the matched cohort, there was no observed difference in 30-day mortality (no-heparin 3.5% vs. heparin 3.0%, P = 0.25), MACCE (no-heparin 7% vs. heparin 6.2%, P = 0.44), and major bleeding (no-heparin 1.9% vs. heparin 1.4%, P = 0.64) between groups. Propensity-score analysis amongst those with TIMI data produced 552 matched pairs. The proportion of cases with TIMI 0 or 1 flow in the infarct-related artery (IRA) was lower among those receiving pre-hospital heparin (66% vs. 76%, P < 0.001) compared to those who did not. CONCLUSION: In this multicentre, propensity-score matched study, the use of pre-hospital heparin by paramedics was safe and is associated with fewer occluded IRAs in patients presenting with STEMI.

Antiplatelet therapy in percutaneous coronary intervention: recent advances in oral antiplatelet agents.

PURPOSE OF REVIEW: Dual antiplatelet therapy with aspirin and clopidogrel, in conjunction with heparin, is the most common antithrombotic strategy in percutaneous coronary intervention (PCI) used to reduce peri-procedural ischaemic complications. However, there remains significant inter-individual variability in post-treatment platelet inhibition with this current established therapy. This review focuses on recent developments in oral antiplatelet agents used in PCI, which promise to overcome, at least in part, current shortfalls. RECENT FINDINGS: Genetic polymorphisms and medication interactions involving CYP3A4 or CYP2C19, patient compliance and higher platelet reactivity in certain subgroups, such as those with diabetes, are important factors contributing to inter-individual variability in post-treatment platelet inhibition. Higher clopidogrel doses have been associated with improved clinical outcomes, especially in those presenting with acute coronary syndrome. Newer agents, namely prasugrel and ticagrelor, have been shown to have greater potency and superior clinical outcomes. However, this comes with a price of increased bleeding complications. SUMMARY: Whereas more potent antiplatelet therapies are associated with improved outcome, balancing the risk of bleeding and peri-procedural ischaemic complications remains a key aspect to consider when choosing among the ever-increasing number of agents available. The role of intravenous glycoprotein IIb/IIIa (GPIIb/IIIa) needs to be re-examined in the current context of such potent oral antiplatelet agents. Further research will hopefully help to determine the preferred antithrombotic strategy in patients undergoing PCI.

Natural History of Spontaneous Coronary Artery Dissection With Spontaneous Angiographic Healing.

OBJECTIVES: Given the uncertainty regarding the degree and prevalence of spontaneous healing following spontaneous coronary artery dissection (SCAD), the aim of this study was to assess the angiographic characteristics of the dissected segments in a large cohort of patients with SCAD who underwent subsequent repeat coronary angiography. BACKGROUND: SCAD is an uncommon yet important cause of myocardial infarction in women. Very little is known about the characteristics of healing of dissected arteries. METHODS: Patients with nonatherosclerotic SCAD followed prospectively at Vancouver General Hospital who underwent repeat angiography were included in this study. Those who underwent percutaneous coronary intervention for SCAD were excluded. Baseline patient demographics and in-hospital and long-term cardiovascular events were recorded. Angiographic characteristics of the SCAD artery at index and repeat angiography were assessed by 2 experienced angiographers. Criteria for angiographic healing were as follows: 1) improvement of stenosis severity from index event; 2) residual stenosis <50%; and 3) TIMI (Thrombolysis In Myocardial Infarction) flow grade 3. RESULTS: One hundred fifty-six patients with 182 noncontiguous SCAD lesions were included. The mean age was 51.5 ± 8.7 years, 88.5% were women, 83.3% were Caucasian, and 75.6% had fibromuscular dysplasia. All patients presented with myocardial infarction. At index angiography, type 2 SCAD was most commonly observed, in 126 of 182 lesions (69.2%); TIMI flow grade <3 was present in 85 of 182 (46.7%); and median lesion stenosis was 79.0% (interquartile range: 56.0% to 100%). Median time to repeat angiography was 154 days (interquartile range: 70 to 604 days), with median residual lesion stenosis improving to 25.5% (interquartile range: 12.0 to 38.8 days), and TIMI flow grade <3 observed in 10 of 182 lesions (5.5%). Angiographic healing occurred in 157 of 182 lesions (86.3%). Of repeat angiography performed ≥30 days post-SCAD, 152 of 160 (95%) showed spontaneous angiographic healing. CONCLUSIONS: The majority of coronary arteries affected by SCAD heal spontaneously on repeat angiography, with apparent time dependency, with the vast majority having complete healing after 30 days from the SCAD event.

The Vancouver 3M (Multidisciplinary, Multimodality, But Minimalist) Clinical Pathway Facilitates Safe Next-Day Discharge Home at Low-, Medium-, and High-Volume Transfemoral Transcatheter Aortic Valve Replacement Centers: The 3M TAVR Study.

OBJECTIVES: The authors sought to prospectively determine the safety and efficacy of next-day discharge using the Vancouver 3M (Multidisciplinary, Multimodality, but Minimalist) Clinical Pathway. BACKGROUND: Transfemoral transcatheter aortic valve replacement (TAVR) is an alternative to surgery in high- and intermediate-risk patients; however, hospital stays average at least 6 days in most trials. The Vancouver 3M Clinical Pathway is focused on next-day discharge, made possible by the use of objective screening criteria as well as streamlined peri- and post-procedural management guidelines. METHODS: Patients were enrolled from 6 low-volume (<100 TAVR/year), 4 medium-volume, and 3 high-volume (>200 TAVR/year) centers in Canada and the United States. The primary outcomes were a composite of all-cause death or stroke by 30 days and the proportion of patients successfully discharged home the day following TAVR. RESULTS: Of 1,400 screened patients, 411 were enrolled at 13 centers and received a SAPIEN XT (58.2%) or SAPIEN 3 (41.8%) valve (Edwards Lifesciences, Irvine, California). In centers enrolling exclusively in the study, 55% of screened patients were enrolled. The median age was 84 years (interquartile range: 78 to 87 years) with a median STS score of 4.9% (interquartile range: 3.3% to 6.8%). Next-day discharge home was achieved in 80.1% of patients, and within 48 h in 89.5%. The composite of all-cause mortality or stroke by 30 days occurred in 2.9% (95% confidence interval: 1.7% to 5.1%), with neither component of the primary outcome affected by hospital TAVR volume (p = 0.51). Secondary outcomes at 30 days included major vascular complication 2.4% (n = 10), readmission 9.2% (n = 36), cardiac readmission 5.7% (n = 22), new permanent pacemaker 5.7% (n = 23), and >mild paravalvular regurgitation 3.8% (n = 15). CONCLUSIONS: Adherence to the Vancouver 3M Clinical Pathway at low-, medium-, and high-volume TAVR centers allows next-day discharge home with excellent safety and efficacy outcomes.

Spontaneous Coronary Artery Dissection: Clinical Outcomes and Risk of Recurrence.

BACKGROUND: Spontaneous coronary artery dissection (SCAD) is underdiagnosed and an important cause of myocardial infarction (MI), especially in young women. Long-term cardiovascular outcomes, including recurrent SCAD, are inadequately reported. OBJECTIVES: This study sought to describe the acute and long-term cardiovascular outcomes and assess the predictors of recurrent SCAD. METHODS: Nonatherosclerotic SCAD patients were prospectively followed at Vancouver General Hospital systematically to ascertain baseline, predisposing and precipitating stressors, angiographic features, revascularization, use of medication, and in-hospital and long-term cardiovascular events. Clinical predictors for recurrent de novo SCAD were tested using univariate and multivariate Cox regression models. RESULTS: The authors prospectively followed 327 SCAD patients. Average age was 52.5 ± 9.6 years, and 90.5% were women (56.9% postmenopausal). All presented with MI; 25.7% had ST-segment elevation MI, 74.3% had non-ST-segment elevation MI, and 8.9% had ventricular tachycardia/ventricular fibrillation. Precipitating emotional stressors were reported in 48.3% and physical stressors in 28.1%. Fibromuscular dysplasia was present in 62.7%, connective tissue disorder in 4.9%, and systemic inflammatory disease in 11.9%. The majority (83.1%) were initially treated medically, with only 16.5% or 2.2% undergoing in-hospital percutaneous coronary intervention or coronary artery bypass graft surgery, respectively. The majority of SCAD patients were taking aspirin and beta-blocker therapy at discharge and at follow-up. Median hospital stay was 3.0 days, and the overall major adverse event rate was 7.3%. Median long-term follow-up was 3.1 years, and overall major adverse cardiac event rate was 19.9% (death rate: 1.2%; recurrent MI: 16.8%; stroke/transient ischemic attack: 1.2%; revascularization: 5.8%). Recurrent SCAD occurred in 10.4% of patients. In multivariate modeling, only hypertension increased (hazard ratio: 2.46; p = 0.011) and beta-blocker use diminished (hazard ratio: 0.36; p = 0.004) recurrent SCAD. CONCLUSIONS: In our large prospectively followed SCAD cohort, long-term cardiovascular events were common. Hypertension increased the risk of recurrent SCAD, whereas beta-blocker therapy appeared to be protective.

Characteristics of extension and de novo recurrent spontaneous coronary artery dissection.

AIMS: Spontaneous coronary artery dissection (SCAD) is an under-recognised and important cause of myocardial infarction in young women. Recurrent SCAD is frequent but poorly understood. We aimed to explore the clinical and angiographic characteristics, and outcomes of recurrent SCAD. METHODS AND RESULTS: Patients with SCAD extension or recurrence prospectively followed at Vancouver General Hospital were included in this retrospective study. SCAD diagnosis was confirmed by two experienced cardiologists. Detailed medical history, baseline demographics, angiographic results, and clinical details of index SCAD and recurrent events were recorded. SCAD extension was defined as angiographic extension of a previously dissected coronary segment, and de novo recurrent SCAD was defined as new spontaneous dissection. We identified 43 patients with SCAD recurrence with mean age 48.9±8.4 years; 38/43 were women, and 32/43 had fibromuscular dysplasia. Nine patients had SCAD extension at median time of five (1-19) days, while 34 patients had de novo recurrent SCAD at median time of 1,487 (107- 6,461) days after the index SCAD event. All SCAD extension patients had worsening of the index dissected segment, with 5/9 involving extension to adjacent segments, while all de novo recurrent SCAD patients had new dissections affecting coronary segments distinct from the index dissection. CONCLUSIONS: De novo recurrent SCAD invariably affected new segments distinct from previously dissected segments.

The First Dedicated Cardiac Rehabilitation Program for Patients With Spontaneous Coronary Artery Dissection: Description and Initial Results.

BACKGROUND: Spontaneous coronary artery dissection (SCAD) is an important cause of myocardial infarction in women, but the role of rehabilitation after SCAD is unclear. METHODS: We designed a dedicated SCAD cardiac rehabilitation (SCAD-CR) program for our SCAD survivors at Vancouver General Hospital. This program encompasses a multidisciplinary approach including exercise rehabilitation, psychosocial counselling, dietary and cardiovascular disease education, and peer group support. Exercise and educational classes were scheduled weekly with a targeted participation of 6 months. Psychosocial counselling, mindful living sessions, social worker and psychiatry evaluations, and peer-group support were offered. RESULTS: We report our first consecutive cohort of 70 SCAD women who joined SCAD-CR from November 2011 to April 2015. The average age was 52.3 ± 8.4 years. Mean participation duration was 12.4 ± 10.5 weeks; 28 completed 6 months, 48 completed ≥ 1 month. At entry, 44 (62.9%) had recurrent chest pains and average metabolic equivalents on exercise treadmill test was 10.1 ± 3.3. At program exit, the proportion with recurrent chest pains was lower (37.1%) and average metabolic equivalents was higher 11.5 ± 3.5 (both P < 0.001). There was a significant improvement in the STOP-D depression questionnaire, with mean scores of 13.0 ± 1.4 before and 8.0 ± 1.7 after the SCAD-CR (P = 0.046). Twenty (28.6%) social worker referrals and 19 (27.1%) psychiatry referrals were made. Mean follow-up was 3.8 ± 2.9 years from the presenting SCAD event, and the major cardiac adverse event rate was 4.3%, lower than our non-SCAD-CR cohort (n = 145; 26.2%; P < 0.001). CONCLUSIONS: This is the first dedicated SCAD-CR program to address the unique exercise and psychosocial needs of SCAD survivors. Our program appears safe and beneficial in improving chest pain, exercise capacity, psychosocial well-being and cardiovascular events.

Prognostic impact of moderate or severe mitral regurgitation (MR) irrespective of concomitant comorbidities: a retrospective matched cohort study.

OBJECTIVE: We sought to objectively quantify the independent impact of significant mitral regurgitation (MR) on prognosis in patients with multiple comorbidities and ascertain the extent to which median survival is affected by increasing comorbidities. METHODS: This was a retrospective matched cohort study using a clinical-echocardiography reporting database linked to a clinical and administrative database in an Australian tertiary hospital. We identified our study cohort (patients with significant MR) and control cohort (without MR) on transthoracic echocardiographies performed between 2005 and 2010. The main outcome measures were mortality and heart failure rehospitalisation. A Cox proportional hazards model was used to adjust for clinical covariates and the 'win ratio' methodology was utilised to estimate the impact of MR on main outcomes. RESULTS: A total of 218 matched patients with and without significant MR were followed-up for 1 year. Significant MR was associated with an adjusted HR for mortality of 1.83 (95% CI 1.28 to 2.62, p<0.001). The win ratio for death and death or heart failure readmission was 0.57 (95% CI 0.40 to 0.78, p=0.0002) and 0.53 (95% CI 0.39 to 0.71, p<0.0001), respectively. Significant MR with left ventricular (LV) systolic dysfunction and age between 75 and 85 years were associated with a substantial reduction in median survival by 2.3 years. Significant MR with LV systolic dysfunction, age beyond 85 and advance comorbidities were associated with a lesser reduction in median survival by 0.2 years. CONCLUSIONS: Significant MR in patients with multiple comorbidities leads to increase in death and heart failure rehospitalisation with reduced estimated median survival. However, its impact diminishes with increasing comorbidities.

The impact of increased age on outcome from a strategy of early invasive management and revascularisation in patients with acute coronary syndromes: retrospective analysis study from the ACACIA registry.

OBJECTIVE: To evaluate the impact of increased age on outcome from a strategy of early invasive management and revascularisation in patients with acute coronary syndromes (ACS). DESIGN: Retrospective analysis of a national Acute Coronary Syndrome registry (ACACIA). SETTING: Multiple Australian (n=39) centres; 25% rural, 52% with onsite cardiac surgery. PATIENTS: Unselected consecutive patients admitted with confirmed ACS, total n=2559, median 99 per centre. INTERVENTIONS: Management was at the discretion of the treating physician. Analysis of outcome based on age >75 years was compared using Cox proportional hazard with a propensity model to adjust for baseline covariates. MAIN OUTCOME MEASURES: Primary outcome was all-cause mortality. Secondary outcomes were bleeding and a composite of any vascular event or unplanned readmission. RESULTS: Elderly patients were more likely to present with high-risk features yet were less likely to receive evidence-based medical therapies or receive diagnostic coronary angiography (75% vs 49%, p<0.0001) and early revascularisation (50% vs 30%, p<0.0001). Multivariate analysis found early revascularisation in the elderly cohort to be associated with lower 12-month mortality hazard (0.4 (0.2-0.7)) and composite outcome (0.6 (0.5-0.8)). Propensity model suggested a greater absolute benefit in elderly patients compared to others. CONCLUSIONS: Following presentation with ACS, elderly patients are less likely to receive evidence-based medical therapies, to be considered for an early invasive strategy and be revascularised. Increasing age is a significant barrier to physicians when considering early revascularisation. An early invasive strategy with revascularisation when performed was associated with substantial benefit and the absolute accrued benefit appears to be higher in elderly patients.