Formation and Evaluation of an Academic Elective for Residents in a Combined Internal Medicine-Pediatrics Residency Program

Background

Recently, there has been increasing focus on skills that are crucial for success in residency that is not explicitly taught. Specifically, the four domains of teaching skills, evidence appraisal, wellness, and education on structural racism have been identified as topics that are important and underrepresented in current resident education curriculums, largely due to time constraints.

Methods

A task force consisting of one post-graduate year 2 (PGY-2) resident, one PGY-4 resident, the Associate Program Director, and the Program Director of the Internal Medicine-Pediatrics residency program was formed to explore current deficiencies in resident curriculum and to research possible solutions. As an intervention, we created and executed a four-week academic elective with dedicated time for upper-level residents to learn and explore the four domains of resident teaching, evidence-based clinical practice, wellness, and anti-racism work. The elective included several clinical sessions dedicated to implementing the skills taught in the elective. The month-long elective completed in January 2021. All residents evaluated each lecture or experience based on how valuable it was to their education on a Likert scale from 1 to 7, with 1 defined as “not valuable at all” and 7 defined as “extremely valuable.”

Results

Residents rated the overall value of teaching in each domain highly. Education and activities in wellness lectures were found to have the highest value-added material (6.20 ± 0.41, n = 18), followed by residents-as-teachers lectures (5.93 ± 0.25, n = 48), anti-racism (5.57 ± 1.11, n = 9), and evidence-based clinical practice (5.18 ± 0.50, n = 43). In addition, each domain was found to have at least one high-yield topic.

Conclusions

We were able to create and execute an academic elective with dedicated time for upper-level residents to develop and utilize valuable skills in teaching, evidence appraisal, wellness, and anti-racism. Future work will focus on refining the curriculum based on resident evaluations and expanding this elective to the Internal Medicine and Pediatrics categorical programs at our institution.

Junctional sarcoplasmic reticulum motility in adult mouse ventricular myocytes

Excitation-contraction (EC) coupling is the coordinated process by which an action potential triggers cardiac myocyte contraction. EC coupling is initiated in dyads where the junctional sarcoplasmic reticulum (jSR) is in tight proximity to the sarcolemma of cardiac myocytes. Existing models of EC coupling critically depend on dyad stability to ensure the fidelity and strength of EC coupling, where even small variations in ryanodine receptor channel and voltage-gated calcium channel-α 1.2 subunit separation dramatically alter EC coupling. However, dyadic motility has never been studied. Here, we developed a novel strategy to track specific jSR units in dissociated adult ventricular myocytes using photoactivatable fluorescent proteins. We found that the jSR is not static. Instead, we observed dynamic formation and dissolution of multiple dyadic junctions regulated by the microtubule-associated molecular motors kinesin-1 and dynein. Our data support a model where reproducibility of EC coupling results from the activation of a temporally averaged number of SR Ca²⁺ release units forming and dissolving SR-sarcolemmal junctions. These findings challenge the long-held view that the jSR is an immobile structure and provide insights into the mechanisms underlying its motility.

Loss of AKAP150 promotes pathological remodelling and heart failure propensity by disrupting calcium cycling and contractile reserve

AIMS

Impaired Ca^2 +cycling and myocyte contractility are a hallmark of heart failure triggered by pathological stress such as hemodynamic overload. The A-Kinase anchoring protein AKAP150 has been shown to coordinate key aspects of adrenergic regulation of Ca²⁺cycling and excitation-contraction in cardiomyocytes. However, the role of the AKAP150 signalling complexes in the pathogenesis of heart failure has not been investigated.

METHODS AND RESULTS

Here we examined how AKAP150 signalling complexes impact Ca²⁺cycling, myocyte contractility, and heart failure susceptibility following pathological stress. We detected a significant reduction of AKAP150 expression in the failing mouse heart induced by pressure overload. Importantly, cardiac-specific AKAP150 knockout mice were predisposed to develop dilated cardiomyopathy with severe cardiac dysfunction and fibrosis after pressure overload. Loss of AKAP150 also promoted pathological remodelling and heart failure progression following myocardial infarction. However, ablation of AKAP150 did not affect calcineurin-nuclear factor of activated T cells signalling in cardiomyocytes or pressure overload- or agonist-induced cardiac hypertrophy. Immunoprecipitation studies showed that AKAP150 was associated with SERCA2, phospholamban, and ryanodine receptor-2, providing a targeted control of sarcoplasmic reticulum Ca²⁺regulatory proteins. Mechanistically, loss of AKAP150 led to impaired Ca²⁺cycling and reduced myocyte contractility reserve following adrenergic stimulation or pressure overload.

CONCLUSIONS

These findings define a critical role for AKAP150 in regulating Ca²⁺cycling and myocardial ionotropy following pathological stress, suggesting the AKAP150 signalling pathway may serve as a novel therapeutic target for heart failure.