Page 13 - Feline Cardiology

NORMAL CARDIOVASCULAR AND RESPIRATORY REFERENCE VALUES FOR THE DOMESTIC CAT

MACROSCOPIC ANATOMY ELECTROCARDIOGRAPHY (Gompf, 1979; Côté, 2010)
Parameter Value References Parameter Value
Heart weight - absolute 17.4 g (range: 11–23 g) Kaneshige, 2006 (n = 10) Rhythm Normal sinus, sinus tachycardia, or sinus bradycardia, depending on context
Heart weight - relative 4.5 ± 0.2 g/kg Kaneshige, 2006 (n = 10)
4.8 ± 1.2 g/kg Fox, 1995 (n = 36) P wave amplitude ≤0.2 mV in leads II and aVF
2
Body surface area m = 0.087 kg 2/3 Bartorelli, 1963 (n = 12) P wave polarity Positive in II and aVF; may be positive in lead I
P wave duration ≤0.04 seconds (inverse correlation with heart rate)
PR interval 0.04–0.09 seconds (inverse correlation with heart rate)
RESPIRATORY PARAMETERS
QRS complex duration ≤0.04 seconds
R wave amplitude ≤0.9 mV in lead II; up to 1 mV in lead V4; no minimum in lead II in the cat
Parameter Value References Mean electrical axis 0–160 degrees (frontal plane); highly variable at least in part due to
Respiratory rate inconsistent limb position and electrode placement
Awake adult 37.5 ± 1.5 breaths/min Orem, 1977 QT interval duration 0.12–0.18 seconds (inverse correlation with heart rate)
Awake kitten 30 breaths/min McMichael, 2008
Asleep adult-nonREM sleep 25.5 ± 0.35 breaths/min Orem T wave amplitude ≤0.3 mV
Asleep adult-REM sleep 41.8 ± 1.9 breaths/min Orem T wave polarity Usually positive in lead II, may be negative or biphasic
Anesthetized adult (chloralose) 20.6 ± 6 breaths/min Nadeau, 1965 Precordial leads R wave ≤1 mV in V2, V4; T wave negative in V10, with R/Q ≤1
Peak inspiratory flow rate
Awake adult 4.324 L/min Orem, 1977 MAGNETIC RESONANCE IMAGING (GENERAL ANESTHESIA) (MacDonald, 2006)
Asleep adult-nonREM sleep 3.03 L/min Orem, 1977
Asleep adult-REM sleep 2.572 L/min Orem, 1977
Tidal volume Parameter Median (range)
Awake adult 33.2 ± 0.73 ml Orem, 1977 Left ventricular mass index (g/kg) 1.6 (1.6 – 1.9)
Asleep adult-nonREM sleep 35.1 ± 0.43 ml Orem, 1977 Left ventricular mass (g) 7.7 (6.7–11.1)
Asleep adult-REM sleep 24.4 ± 0.63 ml Orem, 1977 End-systolic volume (ml) 1.4 (1.1–2.1)
Minute volume End-diastolic volume (ml) 4.0 (3.4–4.9)
Awake adult 1081 ± 25 ml Orem, 1977
Asleep adult-nonREM sleep 883 ± 9.9 ml Orem, 1977 Stroke volume (ml) 2 2.6 (2.3–3.3)
Asleep adult-REM sleep 806 ± 19 ml Orem, 1977 Cardiac index (ml/m ) 75.0 (58–87)
Early filling rate (ml/s) 22.0 (19.6–30)
REM, rapid eye movement Maximum filling rate (ml/s) 23.3 (19.6–28.5)
Mean filling rate (ml/s) 7.0 (5.4–8.7)
Early filling % 85.0 (67.7–92.4)
HEMODYNAMICS
Parameter Value Technique References
Central venous pressure 4.2 ± 1.1 mm Hg Unsedated Lamont, 2001 (n = 7)
Pulmonary arterial pressure (mean) 16.0 ± 0.9 mm Hg Unsedated Lamont, 2001 (n = 7)
Pulmonary capillary wedge pressure 2.9 ± 0.6 mm Hg Unsedated Lamont, 2001 (n = 7)
Cardiac output 1.3 ± 0.09 l/min Thermodilution; unsedated Lamont, 2001 (n = 7)
Cardiac index 108 ± 38 ml/kg/min Thermodilution; isoflurane anesthesia Beaulieu, 2009 (n = 5)
4.42 l/min/m 2 Thermodilution; unsedated Lamont, 2001 (n = 7)
Stroke volume* 6.8 ± 0.565 ml Thermodilution; unsedated Lamont, 2001 (n = 7)
Stroke index* 23.0 ± 2.1 ml/beat/m 2 Thermodilution; unsedated Lamont, 2001 (n = 7)
Systemic vascular resistance* 8506 ± 589 dynes X s/cm 5 Thermodilution; unsedated Lamont, 2001 (n = 7)
Pulmonary vascular resistance* 844 ± 94 dynes X s/cm 5 Thermodilution; unsedated Lamont, 2001 (n = 7)
Rate-pressure product 34232 ± 1063 beats/min X mm Hg Unsedated Lamont, 2001 (n = 7)
RV stroke work index 0.0036 ± 0.00032 g X m/m 2 Thermodilution; unsedated Lamont, 2001 (n = 7)
LV stroke work index 0.042 ± 0.0041 g X m/m 2 Thermodilution; unsedated Lamont, 2001 (n = 7)
*calculated value; RV, right ventricular; LV, left ventricular
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