Effects of the estrous cycle and pregnancy status on cardiovascular variables in healthy bitches

Abstract

This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Risk Factors for Heart Disease in Pet Dogs Attended At a Veterinary Teaching Hospital in Malaysia

“…The exact aetiology remains unknown; however, it was speculated to be related to different stresses acquired throughout life such as pregnancies and fluctuating levels of cardioprotective oestrogen (Youssef 2021). The role of oestrogen in the cardiovascular system of dogs however was unclear, while inconsistent findings on changes in the level of heart rate, cardiac output level, and echocardiographic findings during pregnancy made the exact role of hemodynamic stress on the risk of heart disease in dogs remains unclear (Brooks and Keil 1994;Olsson et al 2003;Abbott 2010;Blanco et al 2011;de Souza et al 2017;Ward et al 2020). However, in neutered dogs, although other cardiac parameters were indifferent, higher blood triglyceride (TG) and very-low-density lipoprotein (vLDL) was found compared to intact dogs, implying the lost role of oestrogen in the synthesis of antioxidant and atherosclerosis-preventing high-density lipoprotein (HDL) (Boonyapakorn et al 2020).…”

Use of drugs in pregnant canine

“…Los cambios fisiológicos más importantes (por sus consecuencias en los procesos farmacocinéticos) se observan a nivel cardiovascular (Pacheco et al 2013). Éstos tienen un ritmo temporal, siendo máximos al día 40 de la preñez; posteriormente comienzan a descender hasta alcanzar los valores de la hembra no preñada el día 20-30 postparto (Ward et al 2020).…”

Effects of pregnancy on electrocardiographic, vasovagal tonus index, and echocardiographic variables in horses

“…The previous studies have demonstrated that hemodynamic adaptations to pregnancy affect maternal echocardiographic variables, increase CO [ 11 ], increase left ventricular wall thickness and left ventricular wall mass [ 25 , 26 ], and increase left ventricular end-diastolic volume and left atrial area throughout pregnancy in women [ 27 ]. The left ventricular free wall in systole increased in normal bitches [ 14 ] and the left ventricular diastolic function changed throughout pregnancy in dogs [ 15 ].…”

“…The changes in cardiovascular function associated with pregnancy are relevant to clinical practice because they may be exacerbated in association with cardiovascular diseases, including hypertension [4,5], diabetes mellitus [6], and congenital heart disease [7] and also lead to the development of pre-eclampsia in women [8][9][10]. Physiological heart murmurs commonly develop during pregnancy in dogs [11]. Studies of pregnant dogs have demonstrated that hemodynamic adaptations to pregnancy affect maternal electrocardiographic parameters [12] and echocardiographic variables, particularly an increase in HR and CO [11,[13][14][15].…”

“…Physiological heart murmurs commonly develop during pregnancy in dogs [11]. Studies of pregnant dogs have demonstrated that hemodynamic adaptations to pregnancy affect maternal electrocardiographic parameters [12] and echocardiographic variables, particularly an increase in HR and CO [11,[13][14][15]. This indicates that the main mechanisms of cardiac adaptation in pregnancy is germane to the activity of autonomic nervous system (ANS) [3] and is associated with a decrease in parasympathetic activity and an increase in sympathetic activity for the increase in blood volume to supply optimal uteroplacental blood flow [9].…”