Detecting and recording cardiac murmurs in clinically healthy puppies in first opinion veterinary practice at the first health check

Abstract

Background: The frequency that cardiac murmurs are identified and recorded in first opinion veterinary practices at the first health check in puppies is unknown. The aims of the study were to assess the agreement between first opinion veterinary practitioners, a veterinary student and a veterinary cardiology specialist on detecting murmurs, and to establish whether abnormal auscultation findings had been recorded in the health certificates of clinically healthy puppies. The study included prospective and retrospective investigations, where the prospectively collected auscultation findings from a veterinary cardiology specialist and a trained veterinary student were compared to auscultation findings recorded by first opinion veterinary practitioners. Results: Cardiac auscultation was performed on 331 client-owned, clinically healthy dogs at two time points: at age 34-69 days by a first opinion veterinary practitioner and at age 45-76 days, on average 9 days later, by a veterinary cardiology specialist and a trained veterinary student. Agreement among the three was compared for the presence of a murmur. The degree of inter-observer agreement was evaluated using Cohen's kappa. Auscultation findings, as noted in the pets' passports, from 331 puppies and 43 different first opinion veterinary practices, were retrospectively reviewed and prospectively compared with auscultation findings from a veterinary cardiology specialist. Agreement between the veterinary cardiology specialist and the first opinion veterinary practitioners was poor (ϰ = 0.01) and significantly different (P < 0.001). First opinion veterinary practitioners had recorded a cardiac murmur in only 1 of the 97 puppies in which the veterinary cardiology specialist detected a murmur. Two-hundred-and-fifty-two puppies were auscultated by both the veterinary cardiology specialist and the student. Their agreement was fair (ϰ = 0.40) and significantly different (P = 0.024). The agreement between the student and a first opinion veterinary practitioner on these 252 puppies was poor (ϰ = 0.03) and significantly different (P < 0.001). Conclusions: This study shows that soft cardiac murmurs are rarely documented during the first veterinary health check in puppies by first opinion veterinary practitioners. Although soft murmurs may not be clinically relevant, finding and recording them is evidence of a carefully performed auscultation. Missing a non-pathological murmur is not of clinical importance; however, missing a pathological murmur could prove detrimental for the individual puppy.

Temporal changes in the presence and intensity of innocent cardiac murmurs in clinically healthy Cairn terrier and Dachshund puppies between 4 and 8 weeks of age

“…Potential reasons for this finding remain unclear as peak blood flow velocities in the left and right ventricular outflow tracts showed no breed‐ or sex‐related differences. Results of published studies evaluating the prevalence of innocent murmurs in Cairn terriers yielded similar outcomes when compared to those of this study 1,3,5 …”

“…Given that the interval between auscultations by the first opinion veterinarian and the cardiology specialist was variable (several days of difference were possible between one test subject and another), it is difficult to hypothesize as to the reason for the variability in their clinical findings. Potential explanations include the spontaneous week‐to‐week variation of the murmurs or the auscultation skills (i.e., experience) of the individual veterinarians 5,9 . However, the fact that the cardiology specialist detected murmurs in more puppies than did the veterinary practitioners (Table 1) suggests that practice and training in cardiac auscultation could be a contributing factor.…”

“…After the first examination, all puppies were subsequently re‐examined weekly under the same environmental, positioning and handling conditions until they were sold to a new owner. Once a murmur was detected, the following variables were noted: timing (systolic, diastolic or continuous), the point of maximal intensity (left or right heart base or apex) and intensity (scale 1–6), as well as other characteristics, such as beat‐to‐beat variability in intensity, and musical character 1–5 . Special attention was also made to auscultating the left axilla to detect potential left‐to‐right shunting patent ductus arteriosus.…”

“…Contrary to most pathological murmurs, innocent murmurs tend to be soft, localized in the left heart base, limited to early systole, and become undetectable spontaneously as the puppy ages 2–4 . A recent study showed a marked difference in the prevalence of soft systolic murmurs in clinically healthy puppies when they were assessed by first opinion veterinary practitioners and, on average, 9 days later by a veterinary cardiology specialist 5 . The factors responsible for this discrepancy remained unclear.…”

“…[2][3][4] A recent study showed a marked difference in the prevalence of soft systolic murmurs in clinically healthy puppies when they were assessed by first opinion veterinary practitioners and, on aver-age, 9 days later by a veterinary cardiology specialist. 5 The factors responsible for this discrepancy remained unclear.…”