Jeong-Ah Ahn

Left Ventricular Diastolic Functional Reserve during Exercise in Patients with Impaired Myocardial Relaxation at Rest

Background: Patients with similar grade diastolic dysfunction at rest may have a spectrum of alterations in diastolic function during exercise. Objective: To evaluate (a) whether exercise could unmask further diastolic abnormalities not evident during rest; (b) whether diastolic functional reserve during exercise is associated with exercise capacity. Methods: 141 subjects (77 male, mean (SD) age 62 (9)) with abnormal left ventricular (LV) relaxation (mitral E/A <0.75) and/or deceleration time >240 ms, underwent graded supine bicycle exercise with simultaneous respiratory gas analysis and two-dimensional and Doppler echocardiographic study. Mitral inflow and annular velocities were measured at rest and during exercise. The LV diastolic function reserve index (DFRI) was calculated. Results: Patients were classified into two groups: group 1 (n = 64), DFRI <13.5; group 2 (n = 77), DFRI ⩾13.5. The ratio of E/E′ to stroke volume was used as an index of ventricular elastance (Ed). No significant differences between the groups in mitral inflow and annular velocities at rest were found. Mean (SD) Ed was not significantly different at rest between the groups (0.19 (0.07) vs 0.18 (0.06), p = 0.29). Ed was significantly higher during exercise in group 1 than in group 2 (25 W, 0.21 (0.09) vs 0.14 (0.04), p<0.001; 50 W, 0.22 (0.10) vs 0.15 (0.04), p<0.001). Group 1 subjects had a shorter exercise duration (8.2 (2.7) vs 9.4 (3.7) min, p = 0.04) and lower peak oxygen consumption (17.5 (4.5) vs 20.2 (5.4) ml/kg/min, p = 0.005). Conclusions: Despite similar mitral flow and annular velocities at rest, different responses to exercise were seen in patients with abnormal LV relaxation at rest. Lower LV diastolic functional reserve was associated with higher ventricular elastance during exercise, and reduced exercise capacity.

Fatal scedosporiosis in multiple solid organ allografts transmitted from a nearly-drowned donor.

Scedosporium spp. is the most common mold infection in pneumonia resulting from near‐drowning. Three fatal scedosporiosis cases developed after solid organ transplantation, probably transmitted from the nearly‐drowned donor. One heart transplant recipient and two kidney transplant recipients developed fatal scedosporiosis following deceased donor transplantation from the same donor, a nearly‐drowned victim of a suicide attempt. Genotypically, indistinguishable strains of Scedosporium auratiacum were recovered from the three recipients. Two liver transplant recipients from the same donor received prophylactic voriconazole without any subsequent signs of infection. To determine the safety of donation from nearly‐drowned donors, a national traceback investigation was also performed of the causes of deaths in all transplant recipients who received organs from drowned donors between 2001 and 2013. Over 13 years, 2600 deceased donor transplants were performed in Korea. Among these 2600 deceased donor transplants, 27 (1%) victims of drowning donated their organs. From these 27 donors, 84 patients received organ transplants and 18 died, including the above three. We found no microbiologic evidence of invasive mold transmission from the nearly‐drowned donors to the other 15 recipients. Although disseminated infection in the donor could not be demonstrated by culture, undiagnosed disseminated donor infection and transmission of Scedosporium spp. should be considered in near‐drowning events.

Gender-Related Difference in Arterial Elastance During Exercise in Patients With Hypertension

Exercise intolerance and heart failure with preserved ejection fraction are common in females. Recently, arterial stiffness has been suggested to be a significant contributor in the development of heart failure. How gender difference affects arterial stiffening and its response to exercise is not well known. We hypothesized that arterial elastance index during exercise would be more abnormal in females with hypertension than males. Arterial elastance index was estimated as arterial end systolic pressure/stroke volume controlled for body surface area and was measured at rest and during graded supine bicycle exercise (25 watts, 3-minute increments) in 298 patients with hypertension (149 males; 149 females; mean age, 59). The subjects were divided into 2 groups by gender. Exercise duration was significantly shorter in females compared to males (692±222 versus 483±128 seconds, P<0.001). Although arterial elastance index at baseline was significantly higher in males, the magnitude of increase was steeper in females with the magnitude of change at 75 W of exercise being significantly higher in females compared to males (0.69±0.83 versus 0.43±0.69, P=0.018). Arterial elastance index at each stage of exercise up to 75 W was independently associated with decreased exercise duration. In conclusion, despite lower arterial elastance index at rest, the increase during exercise was steeper in women with hypertension, suggesting a gender-related difference in dynamic arterial stiffness. The arterial elastance index during exercise was significantly associated with exercise duration in patients with hypertension.