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Schaefer, Jacob J

0000-0002-2349-9700

Mayo Clinic

Mayo Clinic

Citations 2

Exercise as a Therapeutic Strategy for Sarcopenia in Heart Failure: Insights into Underlying Mechanisms
Cho, Jinkyung , Choi, Youngju , Sajgalik, Pavol , No, Mi‐Hyun , Lee, Sang-Hyun , Kim, Sujin , Heo, Jun‐Won , Cho, Eun‐Jeong , Chang, Eunwook , Kang, Ju‐Hee , Kwak, Hyo‐Bum , Park, Dong‐Ho , Schaefer, Jacob J

Cells | October 15, 2020 | Volume: 9 | Issue: 10 | Pages: 2284

10.3390/cells9102284 Get It

Sarcopenia, a syndrome commonly seen in elderly populations, is often characterized by a gradual loss of skeletal muscle, leading to the decline of muscle strength and physical performance. Growing evidence suggests that the prevalence of sarcopenia increases in patients with heart failure (HF), which is a dominant pathogenesis in the aging heart. HF causes diverse metabolic complications that may result in sarcopenia. Therefore, sarcopenia may act as a strong predictor of frailty, disability, and mortality associated with HF. Currently, standard treatments for slowing muscle loss in patients with HF are not available. Therefore, here, we review the pathophysiological mechanisms underlying sarcopenia in HF as well as current knowledge regarding the beneficial effects of exercise on sarcopenia in HF and related mechanisms, including hormonal changes, myostatin, oxidative stress, inflammation, apoptosis, autophagy, the ubiquitin-proteasome system, and insulin resistance.
Left ventricle assist device pulsatility index at the time of implantation is associated with follow-up pulmonary hemodynamics
Sajgalik, Pavol , Kushwaha, Sudhir S. , Olson, Lyle J. , Stulak, John M., Johnson, Bruce D. , Schirger, John A., Schaefer, Jacob J

The International Journal of Artificial Organs | January 27, 2020 | Volume: 43 | Issue: 7 | Pages: 452-460

10.1177/0391398819899403 Get It

HeartMate II left ventricular assist device controllers provide data including pulsatility index, reflecting the relationship between pump function and hemodynamics. We propose that a higher pulsatility index at hospital discharge following implant may be associated with less vascular congestion and improved clinical outcomes. A retrospective analysis of 40 patients (age 59.2 ± 10.3 years) supported with the HeartMate II devices was conducted. Data revealed moderate Pearson correlations between pulsatility index at discharge and right atrial pressure, pulmonary artery systolic pressure, pulmonary artery diastolic pressure, mean pulmonary arterial pressure, and pulmonary capillary wedge pressure, respectively, post-surgery (median of 377 days), demonstrating a stronger relationship when analyzed for the EPC controller (n = 28) only (r = −.57, p < .01; r = −.38, p < .05; r = −.59, p < .01; r = −.47, p = .01 and r = −.53, p < .01, respectively). The pulsatility index derived from the EPC controller was associated with the significant risk of re-hospitalization within 1 and 2 years after the implantation of left ventricular assist device; hazard ratio = 0.557 with 95% confidence interval (0.315–0.983), p = .04 and hazard ratio = .579 (0.341–0.984), p = .04. A higher pulsatility index at discharge was associated with greater volume unloading, lower pulmonary pressures, and lower risk of all-cause re-hospitalizations within 1 and 2 years post-surgery. As such, pump-derived data may provide additional value in predicting left ventricular assist device hemodynamics.