Low-flow, Low-gradient Severe Aortic Stenosis: A Review.

Aortic stenosis (AS) is a common valve pathology experienced by patients worldwide. There are limited population-based studies assessing its prevalence; however, epidemiological studies emphasize that the burden of disease is growing. Recognizing AS relies on accurate clinical assessment and diagnostic investigations. Patients who develop severe AS are often referred to the heart team for assessment of aortic valve intervention. Although echocardiography has traditionally been used to screen and monitor the progression of AS, there can be discordance between measurements in a low-flow state. Such patients may have truly severe AS and potentially derive long-term benefit from aortic valve intervention. Accurately identifying these patients with the use of ancillary testing has been the focus of research for several years. In this article, we discuss the contemporary approaches and challenges in identifying and managing patients with low-flow, low-gradient severe AS.

Comprehensive Review of Complete Versus Culprit-only Revascularization for Multivessel Disease in ST-segment Elevation Myocardial Infarction.

Several organizations have developed guidelines for the management of ST-segment elevation myocardial infarction (STEMI). However, the optimal strategy regarding revascularization in the setting of multivessel disease, specifically with regards to culprit vessel versus complete revascularization, continues to evolve. While previous observational studies promoted culprit vessel-only intervention in patients with STEMI, recent randomized controlled trials suggest potential benefits with multivessel revascularization, either at the time of the index event or in a staged fashion, in patients without cardiogenic shock. This may be due to the known instability of non-culprit lesions in the setting of acute coronary syndrome, and the diffuse coronary processes involved. As additional literature examines culprit vessel versus multivessel revascularization strategies, clinicians continue to be tasked with determining optimal treatment plans for their patients and understanding the factors that promote selected revascularization strategies. This review summarizes and discusses observational studies, randomized control trials and current guidelines in order to evaluate optimal reperfusion strategies for patients presenting with STEMI in the setting of multivessel disease.

Short Durations of Radial Hemostatic Device After Diagnostic Transradial Cardiac Catheterization: The PRACTICAL-2 Randomized Trial.

BACKGROUND: Radial artery occlusion (RAO) is the most common complication following transradial approach (TRA) for cardiac catheterisation. Our aim was to assess if decreasing radial hemostatic device (RHD) time reduces the risk of RAO among individuals receiving small sheath sizes with no adjunctive heparin. METHODS: We randomised 450 individuals undergoing diagnostic cardiac catheterization via TRA to 3 durations of RHD time: 10, 20, or 30 minutes. After these time periods, the RHD was gradually released over 20 minutes. The primary efficacy end point was forearm hematoma grade ≥ 2 (5-10 cm) and the primary safety end point was RAO (as determined by Doppler ultrasound) 1 hour after RHD removal (before discharge). RESULTS: The mean age was 66 years and 64% were male. Five-French sheaths were used in all patients. Hematoma grade ≥ 2 occurred in only 1 patient, who was in the 20-minute group (P = 0.39). RAO occurred in 6.7% of patients in the 10-minute group, 10.7% in the 20-minute group and 6% in the 30-minute group (P = 0.26). CONCLUSIONS: Among patients receiving small-caliber sheaths without adjunctive heparin, the incidence of forearm hematoma and RAO are low. Shorter durations of RHD time did not further reduce the risk of these complications.

Extracorporeal Membrane Oxygenation Utility in Postpartum Patients.

Although extracorporeal membrane oxygenation (ECMO) has been used in many different populations, its use in pregnant or postpartum patients has not been widely studied. This article reviews the ECMO experience in this population at a large urban hospital. Electronic medical records for all pregnant or postpartum patients who required ECMO between 2012 and 2019 were retrospectively reviewed. Data on clinical characteristics, outcomes, and complications were gathered. Comparisons between survivors and nonsurvivors were completed. Ten postpartum patients were identified. The patients presented as follows: four with cardiac arrest, one with a massive pulmonary embolism, three with acute respiratory distress syndrome (ARDS), one with combined ARDS and cardiogenic shock, and one with suspected amniotic embolism. Survival to decannulation was 70%, and survival to discharge was 60%. When comparing survivors vs. nonsurvivors, ECMO survivors tended to have shorter support times vs. nonsurvivors. Otherwise, no differences were noted in age, mechanical ventilation time, or length of stay. Disseminated intravascular coagulation was a common phenomenon in this patient cohort. After initiation of ECMO, elevated serum lactate levels, lower systolic blood pressure, and acute renal failure were predictors of mortality. In a single institution at a large metroplex, we present data regarding the use of ECMO in postpartum patients. ECMO can be successfully used in selected postpartum patients with severe cardiac or respiratory dysfunction. Multidisciplinary collaboration on a regular basis will streamline the ECMO referral in a timely manner. Furthermore, larger studies are indicated to understand the utility of ECMO in larger cohorts.

Apelin increases atrial conduction velocity, refractoriness, and prevents inducibility of atrial fibrillation.

Previous studies have shown an association between elevated atrial NADPH-dependent oxidative stress and decreased plasma apelin in patients with atrial fibrillation (AF), though the basis for this relationship is unclear. In the current study, RT-PCR and immunofluorescence studies of human right atrial appendages (RAAs) showed expression of the apelin receptor, APJ, and reduced apelin content in the atria, but not in plasma, of patients with AF versus normal sinus rhythm. Disruption of the apelin gene in mice increased (2.4-fold) NADPH-stimulated superoxide levels and slowed atrial conduction velocities in optical mapping of a Langendorff-perfused isolated heart model, suggesting that apelin levels may influence AF vulnerability. Indeed, in mice with increased AF vulnerability (induced by chronic intense exercise), apelin administration reduced the incidence and duration of induced atrial arrhythmias in association with prolonged atrial refractory periods. Moreover, apelin decreased AF induction in isolated atria from exercised mice while accelerating conduction velocity and increasing action potential durations. At the cellular level, these changes were associated with increased atrial cardiomyocyte sodium currents. These findings support the conclusion that reduced atrial apelin is maladaptive in fibrillating human atrial myocardium and that increasing apelin bioavailability may be a worthwhile therapeutic strategy for treating and preventing AF.

Effect of a formalised discharge process which includes electronic delivery of prescriptions to pharmacies on the incidence of delayed prescription retrieval.

BACKGROUND: Lack of prescription adherence after discharge from the inpatient hospital setting is a barrier to the delivery of optimal patient care. Non-adherence to medication for cardiac diseases can lead to substantial morbidity, mortality and healthcare costs. Electronic delivery of prescriptions by fax is a potential method of improving patient satisfaction and reducing pharmacy wait times. METHODS: This study was completed in the cardiology inpatient wards at a hospital in London, Ontario, Canada. 'Delayed prescription retrieval' was defined as the retrieval of a prescribed medication by a patient from their local pharmacy after the documented calendar day of discharge. The current discharge process on the cardiology wards was assessed and an initial monitoring period of study participants was completed to determine the baseline delayed prescription retrieval rate (preintervention group). A formalised discharge process, which included electronic delivery of prescriptions to pharmacies by fax, was implemented for study participants (postintervention group). The rate of delayed prescription retrieval was assessed in both groups. RESULTS: 15 of 42 patients (35.7%) in the preintervention group and 9 of 72 (14.3%) in the postintervention group had delayed prescription retrieval suggesting relative and absolute risk reductions of 65% and 23.2% (p=0.0045). Of the participants with delayed prescription retrieval, 100% in the preintervention group and 77.8% in the postintervention group were due a new prescribed medication on the day of discharge. CONCLUSIONS: Patients who experienced a formalised discharge process, which included electronic delivery of prescriptions by fax, at the time of discharge from cardiac inpatient care had a lower rate of delayed prescription retrieval. Future studies are required to examine the impact of formal discharge processes on patient morbidity and mortality.

The use of a sentinel cerebral protection system during Impella CP removal in a patient with left ventricular thrombus.

Percutaneous mechanical circulatory support (pMCS) devices are commonly being utilized for hemodynamic support in patients undergoing high-risk percutaneous coronary interventions or stabilization for those in cardiogenic shock. Left ventricular (LV) to ascending aorta (Ao) rotodynamic pumps such as the Impella devices allow for rapid hemodynamic stabilization or support in such instances. The use of such devices is contraindicated in patients with known LV thrombus. However, it remains unclear on how to manage patients who develop an LV thrombus while on prolonged Impella support. While there are currently no cerebral embolic protection devices (CEPDs) approved for use in conjunction with LV to Ao pMCS devices or other short-term mechanical support devices, there is a theoretical benefit for the use of such technology in the right circumstances. We present a case describing the use of the sentinel cerebral protection system (SCPS) in a patient who developed LV thrombus while on Impella CP support. The use of the SCPS in this patient suggests a potential role for CEPD in prevention of thromboembolism while on Impella support.

Preparing the Next Generation of Code Blue Leaders Through Simulation: What's Missing?

INTRODUCTION: Despite the increasing reliance on simulation to train residents as code blue leaders, the perceived role and effectiveness of code blue simulations from the learners' perspective have not been explored. A code blue Simulation Program (CBSP), developed based on evidence-based simulation principles, was implemented at our institution. We explored the role of simulation in code blue training and the differences between real and simulated code blues from the learner perspective. METHODS: Using a thematic analysis approach and a purposeful sampling strategy, residents who participated in the CBSP were invited to participate in one of the three focus groups. Data were collected through small group discussions guided by semistructured interviews. The interviews were audio-recorded and transcribed. Interview transcripts were coded to assess underlying themes. RESULTS: Thematic analysis revealed that participants believed that the CBSP enhanced preparedness by capturing aspects of real codes (eg, inclusion of precode scenarios with awake patients, lack of readily available information) and facilitating automatization of code blue processes. Despite efforts to develop a high-fidelity simulation, participants noted that they experienced more anxiety, observed more chaos in the environment, and encountered different communication challenges in real codes. CONCLUSIONS: The CBSP enhanced resident preparedness to serve as code blue leaders. Learners highlighted that they valued the CBSP; however, differences remain between simulated and real codes that could be addressed to enhance the fidelity of future simulations.