Page 153 - Clinical Small Animal Internal Medicine

15 Approach to the Patient with Suspected Cardiovascular Disease 121

In dogs with CHF and a chronic reduction of peripheral membranes), systemic veins (jugular veins), peripheral
VetBooks.ir perfusion, a loss of body weight may be apparent. arterial pulses, the precordium (left and right chest wall
Sequential measurements of body weight over time can be
over the heart), palpation of abdomen to identify ascites,
useful to identify subtle weight loss. However, identifica-
tion of weight loss may be problematic if loss of muscle and auscultation of heart and lungs.
mass is masked by concurrent fluid retention.
Mucous Membranes
The mucous membrane color and capillary refill time
Abdominal Distension
are used to evaluate peripheral perfusion. The mucous
Abdominal distension can be caused by a wide variety of membranes of the oral cavity are usually used for this
diseases, both cardiac and noncardiac in origin. In heart purpose, but also ocular and caudal (vaginal or pre-
disease, abdominal distension is the result of right‐sided putial) membranes can be examined. Preferably find-
CHF leading to congestion of abdominal organs (such as ings of caudal membranes should be compared with
the liver) and transudation of fluid into the abdominal findings in the oral cavity. Findings of bluish discol-
cavity. This usually occurs slowly, and remains unno- oration are suggestive of cyanosis (see earlier), dark-
ticed by the owner until quite advanced stages. In other ish red is suggestive of erythrocytosis, and pale
conditions, such as pericardial effusion, the ascites may membranes are suggestive of anemia and/or decreased
develop more rapidly. perfusion. Capillary refill time (CRT) is conducted to
evaluate peripheral perfusion. While commonly per-
formed, CRT is a comparably insensitive method to
Cyanosis
detect abnormal perfusion.
Cyanosis is defined as a blue to blue‐gray discolora-
tion of the mucous membranes as the result of Systemic Veins
increased concentration of deoxygenated hemoglobin.
It can be evident on physical examination and also The jugular veins should be inspected in cases with sus-
described by the owner. Discoloration of the tongue pected heart disease, and clipping or wetting of the fur
and mucous membranes is a common complaint of may be required to visualize these vessels. Distension or
owners suspecting heart disease in their pet, but can pulsations of the jugular veins, while the animal is sitting
be difficult to identify or replicate at the clinic. with the neck moderately extended, are indicative of
Additionally, cyanosis can be difficult to identify increased systemic venous pressure (right‐sided CHF) or
because of pigmentation of the skin and mucous mem- occlusion (most commonly neoplasia or thrombosis) of
branes. Cyanosis in veterinary patients is usually asso- the vessel at the level between the right heart and the jugu-
ciated with severe left‐sided CHF or congenital heart lar vein. Because there is no valve between the right atrium
disease. In case of severe left‐sided CHF, other signifi- and the systemic veins, changes in pressure in the right
cant signs of disease always accompany the cyanosis. atrium are transmitted within the systemic veins, and can
In some cases of congenital heart disease leading to be caused by right atrial contractions at high systemic
right‐to‐left shunting of blood, some animals can venous pressure or tricuspid regurgitation. Sometimes,
have reduced exercise capacity, pelvic limb weakness the carotid arterial pulse is transmitted through the soft
and frequently have to sit down during play or exer- tissues, mimicking a venous pulsation (so‐called false
cise. Depending on the degree of shunting, some of venous pulsations). Differentiation between true and false
these animals can be cyanotic at rest but the cyanosis venous pulsations can be obtained by applying pressure to
becomes more apparent with physical exercise. the jugular vein at a level slightly below the area of the
pulsation. If the pulsation disappears, it is a sign of true
venous pulsation; if it continues, it is a sign of false venous
Physical Examination pulsation.

A thorough physical examination is the foundation for Peripheral Arterial Pulsations
the clinical work‐up in dogs and cats with suspected heart
disease. The examination includes general inspection and The strength and quality of the femoral arterial pulses
observation (e.g., attitude, body condition, mobility, are subjectively assessed by simultaneous palpation of
degree of anxiety, and respiratory pattern), and a thor- both femoral arteries in a standing animal. Sufficient
ough physical examination to identify abnormalities in pressure should be placed on the vessels to occlude them,
other organ systems. The cardiovascular examination so that pulsation is no longer palpable. The pressure is
includes evaluation of the peripheral circulation (mucous then slowly released until maximal pulsation is evident.