#SIRDS IN DOGS SOFTWARE#

Time‐to‐event analyses were carried out in univariate by way of Kaplan‐Meier product limit estimates. Between‐group analyses of baseline variables were performed by using unpaired t‐tests, or the Mann‐Whitney rank sum test as appropriate for the data distribution. Baseline descriptive statistics are presented as mean and standard deviation for normally distributed variables whereas nonnormally distributed variables are presented as median and range. 1 Normality was analyzed by using the Shapiro‐Wilk test.

#SIRDS IN DOGS SOFTWARE#

Sudden death included witnessed sudden death or discovery of deceased animal with no premonitory signs of illness within the past 24 hours.Īll analyses were performed with a commercial statistical software package. Cardiac death was defined as euthanasia or death after onset of signs of congestive heart failure, or sudden death. In addition, dogs that underwent a surgical procedure for palliation of SAS or for which there was no follow‐up information were excluded. Dogs with hemodynamically relevant concurrent congenital cardiac disease such as mitral dysplasia, patent ductus arteriosus, pulmonic stenosis, and valvular or supravalvular aortic stenosis causing clinically relevant pressure or volume overload were excluded from analysis. Dogs with a PG ≥80 mmHg were considered severely affected. Peak velocity of blood flow in the LVOT was measured by continuous‐wave Doppler and used to calculate a PG using the modified Bernoulli equation (∆P = 4V 2), where ∆P = PG and V = peak velocity. 14 Three to 5 measurements were averaged for each variable.

Therefore, the aim of this retrospective study was to determine if the use of beta blocker treatment affects survival in dogs with severe SAS compared to untreated dogs.Īll dogs were diagnosed by or under the supervision of an ACVIM‐board certified cardiologist by using standard transthoracic 2‐dimensional and Doppler echocardiography without sedation.

3īecause of the reported poor prognosis in untreated dogs with severe SAS, studies evaluating the use of beta adrenergic receptor blocking drugs against an untreated control group are lacking. However, they did report survival times of approximately 70 months for surgical correction 12 and 55 months for balloon valvuloplasty, 11 survival times that appear considerably longer than the previously reported 19 months for untreated dogs. 11, 12, 13 Studies that have compared interventional procedures versus beta blocker treatment showed no difference in survival times. Other treatment options for SAS are limited and have included open surgical correction or the use of balloon valvuloplasty. 8, 9 Atenolol, the beta blocker most commonly used in dogs with SAS, is a selective β‐1 receptor antagonist that exerts its effects almost solely on cardiac tissue making it potentially a more attractive choice than less selective beta blockers. Beta blockers have negative chronotropic and inotropic effects and are believed to decrease myocardial oxygen demand. 3Įmpirical treatment with beta blockers commonly is used in the medical management of dogs with severe SAS because of the proposed cardioprotective effects.

6, 7 The prognosis for severely affected dogs traditionally has been considered to be poor based upon a single study evaluating the natural history of SAS that reported a median survival time of 19 months. Treatment for dogs with mild or moderate disease generally is not recommended unless clinical signs develop. 3, 5 Dogs with mild or moderate SAS are considered to have a good prognosis and typically have a normal life span. In general, a PG from 16 to 50 mmHg is considered mild, 50 to 80 mmHg is moderate, and a PG ≥80 mmHg is classified as severe. There is some variability to the classification of SAS.

Severity primarily is classified based upon the pressure gradient (PG) across the stenosis and is divided into 3 categories: mild, moderate, and severe. 3, 4 The prognosis for dogs with SAS is very variable depending on the severity of disease. Subaortic stenosis (SAS) is one of the most commonly diagnosed congenital heart abnormalities of dogs in the United States and Europe 1, 2 and is characterized by an abnormal ridge or ring of fibrous tissue below the aortic valve resulting in decreased cross‐sectional area of the left ventricular outflow tract (LVOT). Abbreviations LVOT left ventricular outflow tract PG pressure gradient SAS subaortic stenosis

Sirds in dogs