Spontaneous Coronary Artery Dissection: New Insights into This Not-So-Rare Condition.

Spontaneous coronary artery dissection (SCAD) is an uncommon but increasingly recognized cause of acute myocardial infarction (MI) among young and middle-aged women and is an important cause of pregnancy-associated MI. Over 90% of SCAD patients are women. Compared to patients with MI caused by atherosclerosis, SCAD patients have fewer cardiovascular risk factors but more often have systemic arteriopathy, most commonly fibromuscular dysplasia. Angiographically, SCAD is characterized by the presence of an intramural hematoma with or without an intimal tear. Accurate recognition of characteristic findings on coronary angiography is critical, as there are important differences in the acute and long-term management of MI caused by SCAD versus atherosclerosis. Acutely, most SCAD patients should be managed conservatively, since percutaneous revascularization is associated with more complications and SCAD-affected vessels usually heal without intervention. Randomized clinical trials and other prospective evaluations are needed, especially to clarify optimal treatment and prevention strategies.

Sex-specific in-hospital outcomes of transcatheter aortic valve replacement with third generation transcatheter heart valves.

BACKGROUND: Sex-based differences in transcatheter aortic valve replacement (TAVR) outcomes have been previously documented. However, whether these differences persist with contemporary third generation transcatheter heart valves (THVs) is unknown. METHODS: We utilized Vizient's clinical database/resource manager (CDB/RM™) to identify patients who underwent TAVR between January 1, 2018 and March 31, 2020 to compare in-hospital outcomes between males and females. The primary endpoint was in-hospital mortality. Secondary endpoints included key in-hospital complications, length of stay, discharge disposition, and cost. Unadjusted, propensity-score matched and risk-adjusted analyses of outcomes were performed. RESULTS: During the study period, 44,280 patients (24,842 males, 19,438 females) underwent TAVR. The primary endpoint of in-hospital mortality was higher in females than in males (1.6 vs. 1.1% p < .001) in unadjusted analysis and persisted following propensity matching (1.6 vs. 0.9%, p < .001) and multivariable logistic regression with various risk-adjustment models. In the most comprehensive model adjusting for age, race, and clinical comorbidities, female sex was associated with 34% greater odds of in-hospital death (95% CI 20-50%, p < .001). Unadjusted and risk-adjusted rates of post-TAVR stroke, vascular complication, and blood transfusion were higher in females. Moreover, females demonstrated longer hospitalizations, higher costs and reduced rates of independent discharge home. CONCLUSION: Sex-based differences in TAVR in-hospital outcomes persist in contemporary practice with third generation transcatheter heart valves. Further research is needed to assess the reasons for these observed disparities and to identify effective mitigation strategies.

Intravascular ultrasound, optical coherence tomography, and fractional flow reserve use in acute myocardial infarction.

BACKGROUND: There are limited data on the use of intravascular ultrasound (IVUS), optical coherence tomography (OCT), and fractional flow reserve (FFR) during acute myocardial infarction (AMI). OBJECTIVES: To assess the temporal trends of IVUS, OCT, and FFR use in AMI. METHODS: A retrospective cohort study from the National Inpatient Sample (2004-2014) was designed to include AMI admissions that received coronary angiography. Administrative codes were used to identify percutaneous coronary intervention (PCI), IVUS, OCT, and FFR. Outcomes included temporal trends, inhospital mortality and resource utilization stratified by IVUS, OCT, or FFR use. RESULTS: In 4,419,973 AMI admissions, IVUS, OCT, and FFR were used in 2.6%, 0.1%, and 0.6%, respectively. There was a 22-fold, 118-fold, and 33-fold adjusted increase in IVUS, OCT, and FFR use, respectively, in 2014 compared to the first year of use. Non-ST-elevation AMI presentation, male sex, private insurance coverage, admission to a large urban hospital, and absence of cardiac arrest and cardiogenic shock were associated with higher IVUS, OCT, or FFR use. PCI was performed in 83.2% of the IVUS, OCT, or FFR cohort compared to 64.2% of the control group (p < .001). The cohort with IVUS/OCT/FFR use had lower inhospital mortality (adjusted odds ratio 0.53 [95% confidence interval 0.50-0.56]), more frequent discharges to home (83.7% vs. 76.8%), shorter hospital stays (4.3 ± 4.4 vs. 5.0 ± 5.5 days) and higher hospitalization costs ($90,683 ± 74,093 vs. $74,671 ± 75,841). CONCLUSIONS: In AMI, the use of IVUS, OCT, and FFR has increased during 2004-2014. Significant patient and hospital-level disparities exist in the use of these technologies.

The prognostic value of non-perfusion variables obtained during vasodilator stress myocardial perfusion imaging.

Myocardial perfusion imaging (MPI) is an established diagnostic test that provides useful prognostic data in patients with known or suspected coronary artery disease. In more than half of the patients referred for stress testing, vasodilator stress is used in lieu of exercise. Unlike exercise, vasodilator stress does not provide information on exercise and functional capacity, heart rate recovery, and chronotropy, and ECG changes are less frequent. These non-perfusion data provide important prognostic and patient management information. Further, event rates in patients undergoing vasodilator MPI are higher than in those undergoing exercise MPI and even in those with normal images probably due to higher pretest risk. However, there are a number of non-perfusion variables that are obtained during vasodilator stress testing, which have prognostic relevance but their use has not been well emphasized. The purpose of this review is to summarize the prognostic values of these non-perfusion data obtained during vasodilator MPI.

Effect of changes in perfusion defect size during serial regadenoson myocardial perfusion imaging on cardiovascular outcomes in high-risk patients.

BACKGROUND: The prognostic value of single-photon emission computed tomography myocardial perfusion imaging (MPI) is well established. There is a paucity of data on the prognostic value of changes in perfusion defect size (PDS) on serial MPIs. METHODS: From the MPI database at the University of Alabama at Birmingham, consecutive patients who underwent two regadenoson stress MPIs between July 2008 and March 2013 were identified. The MPIs were analyzed side-by-side using an automated software program for presence and change in PDS. Improvement in PDS was defined as a reduction ≥5% of left ventricle. A drop in left ventricular ejection fraction (LVEF) was defined as a decrease ≥5%. The primary outcome was a composite of death, myocardial infarction (MI), and coronary revascularization (CR). RESULTS: There were 698 patients (61 ± 11 years, 53% male, 48% diabetes, 25% prior MI, 49% prior CR) who underwent two regadenoson MPIs within 16 ± 9 months for clinical indications. The primary outcome occurred in 167 (24%) patients (8% death, 9% MI, 15% CR) during 24 ± 16 months of follow-up after the second MPI. The MPIs were normal in both studies in 399 (57%, Group 1), showed improvement in 94 (14%, Group 2, PDS 15% ± 16% vs 28% ± 18%, P < .001) and no change or worsening in 205 patients (29%, Group 3, 28% ± 17% vs 20% ± 17%, P < .001). The best outcomes were seen in Group 1 and the worst in Group 3 (log-rank P < .001). Similar trends were seen for the components of the primary outcome (P = .04 for death, P < .001 for MI, P < .001 for CR). In a Cox-regression model that adjusted for baseline factors including PDS and LVEF on initial MPI, the hazard ratios for primary outcome were 2.0 (P = .02) and 3.9 (P < .001) for Groups 2 and 3 compared to Group 1, respectively. In addition, an LVEF drop ≥5% was independently associated with the primary outcome (HR 1.5, P = .01). CONCLUSION: Changes in PDS and LVEF on serial MPIs provide incremental prognostic information to initial and follow-up MPI findings. Lack of improvement or an increase in PDS and a drop in LVEF identify high-risk patients.

Prognostic value of transient ischemic dilation with regadenoson myocardial perfusion imaging.

BACKGROUND: Transient ischemic dilation (TID) of the left ventricle seen on myocardial perfusion imaging (MPI) is sometimes used as a marker of severe coronary artery disease. The prognostic value of TID obtained using regadenoson, a selective adenosine A2A receptor agonist, as a stress agent for MPI has not been studied. METHODS: TID ratio was measured using an automated software program on consecutive patients with normal and abnormal perfusion pattern on regadenoson MPI at a single institution. An abnormal TID was defined as greater than 1.33. The primary outcome was a composite of cardiac death, non-fatal myocardial infarction (MI), and late coronary revascularization (CR, >90 days after MPI). RESULTS: The study population consisted of 887 patients (62 ± 12 years, 66% male, 48% diabetes, 46% prior CR, 75% with abnormal perfusion pattern, left ventricular ejection fraction-LVEF 55 ± 6%). An abnormal TID was present in 51 (6%) patients. Baseline characteristics were not different based on the presence or absence of TID. Early CR (≤90 days) was performed in 11 (22%) patients with vs 92 (11%) patients without TID (P = .04). During a mean follow-up of 29 ± 19 months, the primary outcome occurred in 271 (31%) patients (22% cardiac death, 6% MI, 9% late CR). TID was associated with increased risk of the primary outcome (log-rank P = .017), an association largely driven by late CR. In a Cox proportional model adjusted for multiple variables including perfusion defect size (PDS) and LVEF, the hazard ratio for TID was 1.92 (95% CI 1.20-3.08, P = .007). In the subset of patients with normal perfusion pattern, there was no association between TID and outcomes. CONCLUSIONS: TID on regadenoson MPI carries important prognostic information that is independent from PDS and LVEF, but this association is restricted to patients with abnormal perfusion on imaging.

The prognostic value of regadenoson myocardial perfusion imaging.

BACKGROUND: Regadenoson (REGA), a selective adenosine A2A receptor agonist, is the most widely used stress agent for SPECT myocardial perfusion imaging (MPI) in the United States. The diagnostic accuracy of REGA MPI is comparable to Adenosine MPI, but its prognostic value is not well defined. METHODS: We categorized 1,400 patients (700 consecutive normal and 700 consecutive abnormal REGA-MPIs) into 4 groups based on the perfusion defect size using automated quantitative analysis: Group 1: normal perfusion; Group 2: <10% of left ventricle; Group 3: 10%-20%; Group 4: >20%. The primary outcome was a composite of cardiac death, myocardial infarction (MI), and late coronary revascularization (CR >90 days after MPI). RESULTS: Of the 1,400 patients (42% male, 37% diabetes, 21% heart failure, 26% end-stage renal disease), the primary outcome occurred in 23% (17% cardiac death, 4% MI, 6% late CR) during 46 ± 18 months of follow-up and 8% had early CR (within 90 days of MPI). Early CR occurred in 0.4%, 9%, 17%, and 17% and the primary outcome in 10%, 27%, 31%, and 43% in Groups 1-4, respectively (P < .001 for both). In an adjusted Cox proportional model, the hazard ratio for the primary outcome was 2.68 (1.77-4.06), 3.32 (2.28-4.83), and 4.05 (2.78-5.91) for Groups 2-4 compared to Group 1. CONCLUSION: REGA MPI provides powerful prognostic information that has important implications in patient management and can guide clinical practice.

Smartphones in medicine: emerging practices in an academic medical center.

Advances in mobile phone technology now provide a myriad of resources to physicians' fingertips. However, the medical profession continues to struggle with potential for misuse of these devices. There is a need for better understanding of physicians' uses of smartphones in order to establish guidelines for appropriate and professional behavior. The purpose of the current study was to survey physicians' and medical students' practices concerning smartphone use in the healthcare setting. Physicians and medical students were asked to complete anonymous surveys regarding uses of smartphones within the past month in various healthcare settings. Overall, the participants reported distinctly different patterns in the uses they made of their phones in different settings (P<.001), with most individuals engaging in most behaviors while on break but few using their smartphones while with patients or during procedures. It appears that physicians and medical students make decisions about using their smartphones according to some combination of three considerations: degree of relevance to patient care, the appropriateness of the behavior in front of patients, and the issue of how disruptive that behavior may be.

ECG Case of the Month. Out-of-Hospital Cardiac Arrest. DIAGNOSIS: Atrial fibrillation with a rapid ventricular response (150 beats/minute) and right bundle branch block.

A muscular-appearing 50-year-old man was found down in his home by family members. Paramedics documented pulseless electrical activity and began cardiopulmonary resuscitation that included placement of an endotracheal tube. The resuscitation was continued in the hospital emergency department (ED), and after 20 minutes, an arterial pulse returned. An electrocardiogram (ECG) was obtained (Figure 1). Meanwhile, a past history established that the patient was a personal trainer who seemed fit and healthy until 10 days earlier, when he came to the ED because he had begun to lose his balance and fall frequently. Computed tomography (CT) at that time revealed lytic lesions in the fifth lumbar vertebra and extensive retroperitoneal lymphadenopathy involving the aortic, iliac, and obturator chains and the perirectal region. Arrangements had then been made for outpatient workup of a presumed malignancy.

Risk stratification for coronary artery disease using pharmacological stress tests.

Cardiac stress testing is frequently used for diagnosis of coronary artery disease and for risk stratification which can facilitate decision making and help in the overall management of patients with known or suspected coronary disease. Exercise remains the preferred stress modality and should be performed when feasible but it is often contraindicated, impractical or unable to provide the needed information. In these circumstances pharmacologic stress tests can provide a wealth of prognostic data and should be performed instead of non-diagnostic or suboptimal exercise stress tests. Here we will review the use of pharmacologic stress tests including the indications for ordering them and the different stress agents and imaging modalities that can be utilized with emphasis on practical information that the primary care physician and general practitioner need on a daily basis in their practice.

Risks of Right Heart Catheterization and Right Ventricular Biopsy: A 12-year, Single-Center Experience.

OBJECTIVE: To study the incidence of complications when undergoing right heart catheterization (RHC) and right ventricular biopsy (RVB). METHODS: Complications following RHC and RVB are not well reported. We studied the incidence of death, myocardial infarction, stroke, unplanned bypass, pneumothorax, hemorrhage, hemoptysis, heart valve repair/replacement, pulmonary artery perforation, ventricular arrhythmias, pericardiocentesis, complete heart block, and deep vein thrombosis (primary endpoint) following these procedures. We also adjudicated the severity of tricuspid regurgitation and causes of in-hospital death following RHC. Diagnostic RHC procedures, RVB, multiple right heart procedures alone or combined with left heart catheterization, and complications from January 1, 2002, through December 31, 2013, were identified using the clinical scheduling system and electronic records at Mayo Clinic, Rochester, Minnesota. International Classification of Diseases, Ninth Revision billing codes were used. Registration was queried to identify all-cause mortality. All clinical events and echocardiograms for worsening tricuspid regurgitation were reviewed and adjudicated. RESULTS: A total of 17,696 procedures were identified. Procedures were categorized into those undergoing RHC (n=5556), RVB (n=3846), multiple right heart catheterization (n=776), and combined right and left heart catheterization procedures (n=7518). Primary endpoint was seen in 21.6 and 20.8 of 10,000 procedures for RHC and RVB, respectively. There were 190 (1.1%) deaths during hospital admission and none was related to the procedure. CONCLUSION: Complications following diagnostic RHC and RVB are seen in 21.6 and 20.8 procedures, respectively, of 10,000 procedures and all deaths were secondary to acute illness.

Transcatheter Mitral Valve Repair for Severe Functional Mitral Regurgitation and Cardiogenic Shock.

Patients with acute mitral regurgitation and cardiogenic shock have poor outcomes. Many patients do not qualify for surgery and are left with no treatment options. We present the case of a 76-year-old woman with severe mitral regurgitation, cardiogenic shock, and prohibitive surgical risk who was successfully treated with transcatheter mitral valve edge to edge repair. We also review the existing data that supports transcatheter mitral valve edge to edge repair in this setting.

Percutaneous Axillary Intra-aortic Balloon Pump Insertion Technique as Bridge to Advanced Heart Failure Therapy.

In patients with advanced heart failure (HF), temporary mechanical circulator support (TMCS) is used to improve hemodynamics, via left ventricular unloading, and end-organ function as a bridge to definitive therapy. While listed for cardiac transplantation, use of TMCS may be prolonged, preventing adequate mobility. Here, we describe the technique for placement of a percutaneous axillary intra-aortic balloon pump (IABP) using single-site arterial access to facilitate ambulation and subsequent safe removal without surgery or a closure device. Retrospective review of the experience with this approach at a single institution between September 2017 and February 2020 documented feasibility and safety. Baseline demographics, hemodynamic data, and clinical outcomes were collected. Thirty-eight patients had a total of 56 IABPs placed. There were no significant access site or cerebrovascular complications. One fifth of IABPs (21.4%) had balloon failure or migration, requiring placement of a new device, though no patients had significant complications from balloon failure. The majority (81.6%) of patients in the cohort on axillary IABP support were ambulatory and ultimately received the intended therapy (63.2% transplant, 13.2% durable left ventricular assist device, 5.3% other cardiac surgery). Percutaneous, axillary IABP is feasible and associated with an acceptable complication rate as a bridge to definitive therapy.

Coronary Artery Fistulas: Indications, Techniques, Outcomes, and Complications of Transcatheter Fistula Closure.

Coronary artery fistulas (CAFs) are rare coronary anomalies that are usually diagnosed incidentally with cardiac imaging. Small CAFs are generally asymptomatic and can close over time, while some untreated medium or large CAFs can enlarge, leading to clinical sequelae such as cardiac chamber enlargement or myocardial ischemia. With the advancement of transcatheter equipment and techniques, CAFs have been increasingly closed using a percutaneous approach. However, the procedure is not free of limitations given the risk for myocardial infarction, device embolization, and fistula recanalization. In this review, the authors illustrate the contemporary procedural considerations, techniques, and outcomes of transcatheter CAF closure.

Diagnostic Cardiovascular Imaging and Therapeutic Strategies in Pregnancy: JACC Focus Seminar 4/5.

The prevalence of cardiovascular disease (CVD) in pregnancy, both diagnosed and previously unknown, is rising, and CVD is a leading cause of maternal morbidity and mortality. Historically, women of child-bearing potential have been underrepresented in research, leading to lasting knowledge gaps in the cardiovascular care of pregnant and lactating women. Despite these limitations, clinicians should be familiar with the safety of frequently used diagnostic and therapeutic interventions to adequately care for this at-risk population. This review, the fourth of a 5-part series, provides evidence-based recommendations regarding the use of common cardiovascular diagnostic tests and medications in pregnant and lactating women.

Correlation of Intravascular Ultrasound and Instantaneous Wave-Free Ratio in Patients With Intermediate Left Main Coronary Artery Disease.

BACKGROUND: There is great degree of interobserver variability in the visual angiographic assessment of left main coronary disease (LMCD). Fractional flow reserve and intravascular ultrasound are often used in this setting. The use of instantaneous wave-free ratio (iFR) for evaluation of LMCD has not been well studied. The aim of this study is to evaluate the use of iFR in the assessment of angiographically intermediate LMCD. METHODS: This is an international multicenter retrospective observational study of patients who underwent both iFR and intravascular ultrasound evaluation for angiographically intermediate LMCD. An independent core laboratory performed blinded off-line analysis of all intravascular ultrasound data. A minimum lumen area of 6 mm2 was used as the cutoff for significant disease. RESULTS: One hundred twenty-five patients (mean age, 68.4±9.5 years, 84.8% male) were included in this analysis. Receiver operating curve analysis showed that an iFR of ≤0.89 identified minimum lumen area <6 mm2 with an area under the curve of 0.77 (77% sensitivity, 66% specificity; P<0.0001). Among the 69 patients without ostial left anterior descending artery or left circumflex artery disease, receiver operating curve analysis showed that an iFR of ≤0.89 identified minimum lumen area <6 mm2 with an area under the curve of 0.84 (70% sensitivity, 84% specificity; P<0.0001). The correlation was not significantly different when the body surface area was considered. CONCLUSIONS: In this study, in patients with intermediate LMCD, iFR of ≤0.89 correlates with intravascular ultrasound minimum lumen area <6 mm2 regardless of body surface area. The current study supports the use of iFR for the evaluation of intermediate LMCD.

Heart failure with preserved ejection fraction: Similarities and differences between women and men.

The syndrome of heart failure (HF) with preserved ejection fraction (HFpEF) is now recognized to account for up to half of HF cases and is the dominant form of HF in older adults, especially women. Multiple factors conspire in this predilection of HFpEF for older women. This review will discuss the epidemiology, pathophysiology, prognosis, and treatment of HFpEF with emphasis on the similarities and differences in cardiovascular aging changes, and the differential impact of comorbidities in women versus men. Responses to pharmacologic and lifestyle interventions are also reviewed. We conclude by suggesting future directions for both prevention and treatment of this common and highly morbid cardiovascular disorder.

Safety of Revascularization Deferral of Left Main Stenosis Based on Instantaneous Wave-Free Ratio Evaluation.

OBJECTIVES: The aim of this study was to assess the long-term clinical outcomes of patients with left main coronary artery (LM) stenosis in whom treatment strategy was based on the instantaneous wave-free ratio (iFR). BACKGROUND: The overall safety of iFR to guide revascularization decision making in patients with stable coronary artery disease has been established. However, no study has examined the safety of deferral of revascularization of LM disease on the basis of iFR. METHODS: This multicenter observational study included 314 patients in whom LM stenosis was deferred (n = 163 [51.9%]) or revascularized (n = 151 [48.1%]) according to the iFR cutoff ≤0.89. The primary endpoint was a composite of all-cause death, nonfatal myocardial infarction, and ischemia-driven target lesion revascularization. The secondary endpoints were each individual component of the primary endpoint and also cardiac death. RESULTS: At a median follow-up period of 30 months, the primary endpoint occurred in 15 patients (9.2%) in the deferred group and 22 patients (14.6%) in the revascularized group (hazard ratio: 1.45; 95% confidence interval: 0.75 to 2.81; p = 0.26), indicating no evidence of a significant difference between the 2 groups. For the secondary endpoints, findings in the iFR-based deferral and revascularization groups were as follows: all-cause death, 3.7% versus 4.6%; cardiac death, 1.2% versus 2.0%; nonfatal myocardial infarction, 2.5% versus 5.3%; and target lesion revascularization, 4.3% versus 5.3% (p > 0.05 for all). CONCLUSIONS: Deferral of revascularization of LM stenosis on the basis of iFR appears to be safe, with similar long-term outcomes to those in patients in whom LM revascularization was performed according to iFR values.

Transcatheter Mitral Valve Replacement: An Update on the Current Literature.

PURPOSE OF REVIEW: The purpose of this review was to evaluate the complexities and challenges associated with transcatheter mitral valve replacement and review the existing data. RECENT FINDINGS: Many patients with mitral valve disease are not candidates for cardiac surgery and are in need of less invasive transcatheter therapies. The first transcatheter mitral valve replacement (TMVR) in a native valve was performed in 2012. However, the complexities and variability of the mitral valve anatomy and its relationship to neighboring structures have resulted in slower progress with this new therapy compared to the rapid uptake that has occurred with transcatheter aortic valve replacement. TMVR can be applied to degenerated prosthetic valves and annuloplasty rings or to a wide variety of native mitral valve disease. In cases of degenerated bioprosthetic valves, annuloplasty ring, and native valve mitral annular calcification, transcatheter heart valves (THVs) designed for the aortic position can be implanted with high procedural safety and success rates. In the case of native valve mitral regurgitation, the complexities have led to the development of several TMVR systems for native valve disease with different anchoring mechanisms and geometry; all are currently investigational and none are FDA approved at this time. It is clear from the initial experience with TMVR that careful patient selection and pre-procedural planning are necessary to maximize benefit and avoid complications. TMVR is an exciting complex therapy offering promise for patients who cannot be treated with existing techniques. The key to success will be a combination of appropriate patient selection, careful comprehensive pre-procedural planning, rising new technologies, as well as further research to appropriately define and mitigate the risks associated with the procedure.