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Pulse Abnormalities 845

coronary artery is suspected, a left-sided injec- feasible, exercise restriction and beta-blocker PEARLS & CONSIDERATIONS
tion should be performed to assess coronary therapy are frequently recommended to Comments
VetBooks.ir rupture during balloon valvuloplasty. These sudden death, although the latter benefit Careful auscultation over the left heart base Diseases and Disorders
control clinical signs and reduce the risk of
anatomy due to the risk of coronary artery
remains unproven.
abnormalities are most commonly reported
is key to detection, especially in animals with
in boxers and bulldog breeds.
Possible Complications no clinical signs.
TREATMENT In severe obstruction, progressive right ven- Prevention
tricular hypertrophy, tricuspid regurgitation, Dogs with confirmed pulmonic stenosis should
Treatment Overview and increased right atrial pressure may result in not be used for breeding.
The goal of treatment is to reduce clinical signs worsening exercise tolerance, recurrent syncope,
and myocardial workload to decrease the risk arrhythmias, CHF, and sudden death. Technician Tips
of CHF and sudden death. Common signs of disease progression include
Recommended Monitoring the development or worsening of exercise
Acute General Treatment For dogs not undergoing interventional or intolerance or arrhythmias, increasing frequency
• Treatment is not necessary in animals with surgical treatment, serial echocardiography of syncope, and development of clinical signs
mild or moderate stenosis that is not associ- is recommended to monitor progressive of right-sided CHF, such as ascites. Situations
ated with clinical signs. right ventricular hypertrophy or right atrial likely to result in increased sympathetic tone
• Animals with severe, fixed obstruction and/or enlargement. The pressure gradient sometimes (e.g., stress, excitement, exertion) should be
clinical signs referable to pulmonic stenosis increases as puppies grow toward maturity. After avoided in cases of severe pulmonic stenosis
(e.g., exercise intolerance, syncope or signs interventional or surgical treatment, short- and because they are likely to exacerbate clinical
of right-sided CHF) should be referred for long-term success is assessed by longitudinal signs. Calm, gentle handling is paramount,
interventional or surgical reduction in pres- echocardiographic monitoring of the pressure especially for cats.
sure gradient. The precise approach chosen gradient. Detected arrhythmias should be
(e.g., balloon valvuloplasty, pulmonary patch assessed and monitored electrocardiographically. Client Education
graft) depends on the anatomic location and Puppies with persistent heart murmurs often
characteristics of the lesion and presence or PROGNOSIS & OUTCOME benefit from referral to a veterinary cardiologist
absence of concurrent congenital defects. for echocardiography. Balloon valvuloplasty or
• Type 1 valvular lesions are most amenable • Animals with mild pulmonic stenosis often surgical correction should be offered in cases of
to balloon valvuloplasty. Surgery may be have a good quality of life and relatively severe stenosis. Owners should be warned of
necessary in cases of annular hypoplasia or normal life expectancy. the risk of right-sided CHF or sudden death
significant subvalvular obstruction. • Prognosis is guarded for dogs with severe in these cases.
• Dynamic obstructions that are exacerbated obstructions due to the risk of right-sided
by increased sympathetic tone may respond CHF or sudden death. Prognosis is also nega- SUGGESTED READING
to adrenergic beta-receptor blockade (e.g., tively affected by significant right ventricular Stafford JM, et al: Pulmonic stenosis in dogs: balloon
atenolol 0.5-1.5 mg/kg PO q 12h). These hypertrophy or tricuspid regurgitation. valvuloplasty improves outcome. J Vet Intern Med
dynamic obstructions may persist after • Balloon valvuloplasty improves outcome, 18:656-662, 2004.
interventional or surgical treatment for fixed especially in those patients in which severity AUTHOR: Melanie Hezzell, VetMB, MA, PhD, DACVIM
stenosis, requiring ongoing treatment. is reduced into the mild to moderate range. EDITOR: Meg M. Sleeper, VMD, DACVIM
• In cases of severe obstruction in which • Restenosis occurs infrequently after balloon
interventional or surgical treatment is not valvuloplasty.

Pulse Abnormalities Client Education
Sheet

BASIC INFORMATION ASSOCIATED DISORDERS pulse amplitude alternates between a strong
A detailed differential diagnosis is discussed pulse and a weak or absent pulse)
Definition on p. 1275. • Variation in pulse rhythm: tachyarrhythmias
The arterial pulse is produced by the fluctuation • Reduced pulse amplitude (hypokinetic pulse): (atrial fibrillation, premature beats) or brady-
between diastolic and systolic arterial pressure decreased cardiac output or left ventricular arrhythmias (second-degree atrioventricular
and can be palpated as an impulse in superficial outflow tract obstruction. With aortic or block)
arteries, such as the femoral artery. Pulse deficit subaortic stenosis, the pulse may be decreased • Regular variation in pulse amplitude:
refers to a heartbeat that is heard on auscultation and delayed (pulsus parvus et tardus). exaggerated effect of respiration: pulsus
or felt on the chest wall but does not generate • Increased pulse amplitude (hyperkinetic paradoxus (pericardial effusion with cardiac
a palpable arterial pulse. pulse): increased stroke volume or decreased tamponade). The pulse is stronger during
diastolic arterial pressure. Example: diastolic expiration and weaker during inspiration.
Synonyms runoff through a patent ductus arteriosus • Regional variation in pulse amplitude: arterial
• Hyperkinetic pulse: strong, bounding, or causes a greater difference between systolic thromboembolism (feline myocardial disease,
water-hammer pulse and diastolic pressures (greater pulse infective endocarditis, hypercoagulable
• Hypokinetic pulse: weak or thready pulse pressure) and a correspondingly stronger states)
pulse.
Epidemiology • Pulse deficits (missing pulses compared with Clinical Presentation
SPECIES, AGE, SEX cardiac auscultation): tachyarrhythmias, HISTORY, CHIEF COMPLAINT
Dogs and cats of either sex and any age severe myocardial failure (pulsus alternans; Varies widely, depending on underlying cause

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