Skip to content
PawLabel
Sign in
anatomy guide

Dog cardiovascular system — anatomy overview

Overview of the canine heart and blood vessels — a four-chambered heart driving separate pulmonary and systemic circulations throughout the body.
General educational reference only — not clinical or veterinary advice. Anatomy varies between individual animals; consult a licensed veterinarian for any health concern.

The heart

The dog has a four-chambered heart with two atria and two ventricles separated by valves that keep blood moving in one direction. The right side pumps blood to the lungs, and the left side pumps oxygenated blood to the rest of the body. A specialized electrical conduction system sets and coordinates the heartbeat.

Pulmonary and systemic circulation

Blood follows two linked loops: the pulmonary circuit carries blood between the heart and lungs for gas exchange, and the systemic circuit delivers oxygen and nutrients to tissues. Arteries carry blood away from the heart, and veins return it. This double-loop arrangement keeps oxygen-rich and oxygen-poor blood separate.

Blood and vessels

Blood transports oxygen, nutrients, hormones, and immune cells while carrying away carbon dioxide and waste. Capillaries are the smallest vessels, where exchange with tissues actually occurs. Heart rate in dogs varies with body size, fitness, and activity, with smaller dogs generally having faster resting rates.

Sources

More Dog anatomy

Digestive systemSkeletal systemRespiratory systemUrinary systemIntegumentary systemNervous systemDental anatomy

Other species

Cat digestive system — anatomy overviewCat skeletal system — anatomy overviewCat cardiovascular system — anatomy overviewCat respiratory system — anatomy overviewCat urinary system — anatomy overviewCat integumentary system — skin and coat anatomy overviewCat dental anatomy — teeth overviewRabbit digestive system — hindgut fermentation and cecotrophyRabbit dental anatomy — continuously growing (elodont) teethRabbit skeletal system — lightweight bones and a fragile spineFerret digestive system — short-gut obligate carnivoreFerret respiratory system — anatomy overviewGuinea pig digestive system — hindgut fermenter with vitamin-C dependenceGuinea pig dental anatomy — open-rooted, continuously growing teethParrot respiratory system — air sacs and flow-through lungsParrot digestive system — crop, gizzard, and cloacaParrot skeletal system — pneumatic bones and a flight frameBearded dragon digestive system — anatomy overviewBearded dragon skeletal system — anatomy overviewBearded dragon thermoregulation — ectothermy and skinSnake digestive system — a highly distensible carnivore gutSnake skeletal system — vertebrae and ribsTortoise skeletal system — carapace, plastron, and fused ribsTortoise digestive system — beak, gut, and hindgut fermentationBearded dragon respiratory system — glottis, trachea, and faveolar lungsParrot urinary system — avian kidneys, ureters, and uric acidLeopard gecko digestive system — an insectivore's gutParrot cardiovascular system — avian heart and circulationTurtle skeletal system — shell, girdles, and neck retractionBearded dragon dental anatomy — acrodont and pleurodont teethSnake respiratory system — glottis, tracheal lung, and one functional lungLeopard gecko skeletal system — limbs and tail autotomyAxolotl respiratory system — external gills, lungs, and skinHorse digestive system — hindgut fermenter with a large colonSnake integumentary system — scales, ecdysis, and the spectacleTortoise respiratory system — breathing inside a rigid shellBetta respiratory system — gills and the labyrinth organGoldfish digestive system — pharyngeal teeth and no true stomachGoldfish respiratory system — gill arches, lamellae, and countercurrent exchangeParrot integumentary system — feathers, tracts, and the preen glandSnake cardiovascular system — a three-chambered heart along the bodyLeopard gecko integumentary system — skin, shedding, and toes without padsChinchilla dental anatomy — elodont teeth and continuous eruptionChinchilla digestive system — a sacculated cecum and an exceptionally long colonAfrican pygmy hedgehog integumentary system — spines, mantle, and the orbicularis muscleRat dental anatomy — continuously growing incisors and rooted molars

Explore

All anatomy guidesToxic foods & substancesPet-food allergens