Retrospective evaluation of the ST segment electrocardiographic features in 180 healthy dogs

Abstract

Normal features of the ST segment are poorly characterised in dogs. This study aimed to describe ST segment characteristics in a population of healthy dogs.Materials and MethOds: Medical records were reviewed to identify healthy dogs that underwent an electrocardiogram. Several ST segment qualitative parameters were evaluated: presence/absence of deviation, type of deviation (depression/elevation) and morphological patterns of depression (horizontal, downsloping, upsloping and sagging) and elevation (horizontal, concave and convex). Moreover, the amplitude of ST segment depression/elevation was measured. The potential effect of sex, bodyweight, age and somatotype on the presence/absence of ST segment deviation was evaluated through binary logistic regression.results: One hundred and eighty dogs were enrolled. The deviation was evident in 43 of 180 dogs (23.9%), among which 36 showed depression and seven showed elevation. The median depression amplitude was 0.1 (range 0.05 to 0.3) mV. The mean elevation amplitude was 0.136 ±0.055 mV. Concerning depression morphology, the horizontal pattern was overrepresented, followed by the downsloping and upsloping ones.Concerning elevation morphology, all dogs showed a concave pattern. No meaningful effect of sex, bodyweight, age and somatotype on the presence/absence of ST segment deviation was documented. clinical significance: Normal features of canine ST segment were described and made available for clinical use.

Evaluating the accuracy of a six‐lead smartphone‐based electrocardiographic device compared with standard electrocardiography in brachymorphic dogs

“…The agreement between the two devices for each quantitative variable is reported in Table 2 and Figure 3. With both devices, most of these variables were within the generic reference intervals, 25,26,[41][42][43] with the only exception being the QRS complex MEA, as a trend towards a left shift was observed with both devices. Indeed, with the st-ECG machine, the mean QRS complex MEA was 47.5 • (0 • −100 • ) and 31 of 75 (41.3%) dogs showed a left shift (median value of the QRS complex MEA among these subjects 32 • [0 • −39 • ]).…”

“…Both the ST segment and the T wave represent two ECG parameters traditionally neglected in the veterinary literature, whose clinical relevance has been highlighted in small animals in recent years [47][48][49][50] and whose reference intervals have recently been documented in dogs. 41,42 The interpretation of these parameters is essential for a complete ECG analysis, as ventricular repolarisation is as important as depolarisation. Regrettably, previous studies evaluating digital ECG devices did not analyse their accuracy in the assessment of these ECG components.…”

“…Subsequently, analysis of the main ECG variables was performed as previously described. 26,41,42 Specifically, these included the duration, amplitude and MEA in the frontal plane of the P-wave; the PQ interval duration; the duration and MEA of the QRS complex; the Q wave, R wave and S wave amplitudes; the presence/absence of ST segment deviation and its amplitude; the polarity and amplitude of the T wave; and the duration of the QT interval. Three representative consecutive beats were used to measure various ECG variables, and the results were averaged for each variable.…”

Transient myocardial thickening associated with acute myocardial injury and congestive heart failure in two Toxoplasma gondii-positive cats

“…A six-lead surface electrocardiogram showed atrial standstill associated with a ST-segment elevation, suggestive of possible concomitant myocardial ischaemia ( Figure 1 ). 18 Transthoracic echocardiography was subsequently performed ( Figure 2 , Table 1 ), which showed diffuse asymmetric LVMT, LA dilation with decreased LA fractional shortening, and an enlarged and hypokinetic LA appendage. 19 – 21 …”

“…A six-lead surface electrocardiogram showed atrial standstill associated with a ST-segment elevation, suggestive of possible concomitant myocardial ischaemia (Figure 1). 18 Transthoracic echocardiography was subsequently performed (Figure 2, Table 1), which showed diffuse asymmetric LVMT, LA dilation with decreased LA fractional shortening, and an enlarged and hypokinetic LA appendage. [19][20][21] The cat was hospitalised under continuous electrocardiographic monitoring and treated with furosemide (1 mg/kg IV q8h), pimobendan (0.25 mg/kg PO q12h) and clopidogrel (18.75 mg/cat PO q24h).…”