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Hypertrophic cardiomyopathy (HCM) is a common form of cardiomyopathy in cats, and heart failure occurs as diastolic dysfunction progresses. HCM in cats is broadly classified as non-obstructive and obstructive hypertrophic cardiomyopathy, depending on the presence or absence of outflow tract obstruction. Measurement of the intraventricular pressure differences (IVPD) using color M-mode (CMM) has attracted attention as a reliable diastolic index as it correlates with catheterization, the gold standard for the assessment of diastolic performance. Because IVPD is affected by the size of the heart, the intraventricular pressure gradient (IVPG) index, which is unaffected by heart size, is by calculated by dividing IVPD by LV length. In the present study, CMM IVPG was used to non-invasively assess diastolic impairment in cats with obstructive hypertrophic cardiomyopathy. This study was conducted on 10 control cats and 18 cats in the HCM group. Although no severe left atrial enlargement was observed in the HCM group, the basal IVPG was significantly increased in the HOCM group compared to the control group. Although IVPD typically suggests impaired diastolic function and reduced ventricular compliance, the significant increase observed in the HOCM group compared to controls may suggest an indirect elevation in left atrial pressure, likely secondary to left ventricular outflow tract obstruction. The increase in IVPG in HOCM, as shown in this study, is a pathological effect of left ventricular outflow tract obstruction that cannot be detected by conventional echocardiographic indices, and evaluating IVPG is useful to evaluate cardiac function from a perspective that differs from conventional methods.

Chymase is a protease stored in mast cell granules that produces angiotensin II (ANG II) from angiotensin I (ANG I) and is associated with tissue injury, inflammation, and remodeling, especially involving the cardiovascular system. As cardiovascular events occur, chymase is activated by degranulation to the extracellular matrix. Although chymase has been suggested to be associated with cardiovascular disease progression, there are not enough reports in veterinary medicine. Patent ductus arteriosus (PDA) is a common congenital cardiac disease in veterinary medicine. Almost all cases of PDA can be treated surgically to prevent the development of congestive heart disease and/or pulmonary hypertension. The aims of the present study were to measure chymase activity before and after PDA occlusions, and to investigate the relationships between the congestive and hemodynamic states of PDA and chymase activity. In the present study, 17 puppies diagnosed with PDA were included and all puppies completely recovered to the level of healthy dogs. Chymase activity significantly decreased at 2 months after the operation, along with the echocardiography parameters of congestion. Therefore, plasma chymase activity may be useful as a novel predictor for understanding the hemodynamics of PDA in veterinary medicine.

Protamine, an antagonizing agent to heparin, is indispensable for dogs undergoing cardiopulmonary bypass. Protamine-induced hypotension (PIH) during cardiac anesthesia has been reported in humans. The purpose of this study was to describe the hemodynamic effect of protamine administration in dogs during cardiac surgery in clinical cases. Study design: Retrospective, clinical, cohort study. A total of 14 client-owned dogs who suffered heart failure due to medically uncontrolled myxomatous mitral valve disease (MMVD) were included in this study. The severity of MMVD was classified according to American College of Veterinary Internal Medicine staging (ACVIM: stage B2, C, D) and dogs undergoing mitral valve surgery. Records with clinical data for dogs treated between July 2019 to August 2020 were examined for age, sex, breed, body weight, concurrent diseases, hospitalization, anesthetic record, and mortality within 3 months after the operation. PIH was defined as mean arterial pressure (MAP) lowered by 20% of that before protamine infusion. To evaluate the effect of protamine on hemodynamic variables, each of the other values was compared with values at the beginning of protamine infusion. MAP decreased by 41.0 and 45.7% in two dogs (14.3%) compared with pressure before protamine infusion. Others did not show obvious alteration in hemodynamic variables. Epinephrine treatment alleviated hypotension in one dog. Another dog with systemic hypotension concomitant with elevated central venous pressure did not respond to epinephrine treatment and a reboot of extracorporeal circulation was required. Reheparinization and reinstitution of cardiopulmonary bypass successfully resuscitate the second dog. In conclusion, clinicians should alert the incidence of severe hypotension even with slow protamine infusion following canine cardiac surgery. This study also provides two effective treatments for catastrophic hypotension during protamine infusion.

A ruthenium-catalyzed asymmetric arylation of aliphatic aldehydes and α-ketoesters with arylboronic acids has been developed, giving chiral alkyl(aryl)methanols and α-hydroxy esters in good yields. The use of a chiral bidentate phosphoramidite ligand (Me-BIPAM) achieved excellent enantioselectivities.