The Correlation of Decreased Heart Rate Recovery and Chronotropic Incompetence with Exercise Capacity in Idiopathic Pulmonary Arterial Hypertension Patients
Table 1
The demographics, PFT, and CPET of IPAH variables in patients and healthy subjects.
IPAH patients
Control subjects
Demographics
58
25
Sex (F/M)
37/21
13/12
>0.05
Age (y)
35.2 ± 13.8
40.1 ± 15.4
>0.05
BMI (kg/m2)
22.5 ± 4.2
22.3 ± 3.4
>0.05
PFT
FVC (L)
2.9 ± 0.9
3.7 ± 0.9
<0.01
FVC% pred
81.9 ± 15.4
97.2 ± 13.1
<0.01
FEV1 (L)
2.4 ± 0.7
3.0 ± 0.7
<0.01
FEV1% pred
77.4 ± 14.8
96.2 ± 11.5
<0.01
FEV1/FVC (%)
80.2 ± 7.5
83.2 ± 6.7
>0.05
FEF25 (L/s)
4.7 ± 2.0
6.0 ± 1.8
<0.05
FEF25%
72.5 ± 22.0
94.6 ± 11.4
<0.01
FEF50 (L/s)
2.8 ± 1.4
4.2 ± 1.3
<0.01
FEF50%
66.0 ± 25.7
102.3 ± 29.5
<0.01
FEF75 (L/s)
1.0 ± 0.8
2.0 ± 1.8
<0.05
FEF75%
49.8 ± 27.9
89.5 ± 32.7
<0.01
DLco (% pred)
65.1 ± 11.3
92.3 ± 11.0
<0.01
CPET
Base line HR (bpm)
85.4 ± 12.0
84.0 ± 10.7
>0.05
Peak HR (bpm)
140.7 ± 21.3
167.4 ± 17.1
<0.01
ΔHR (bpm)
55.3 ± 21.3
83.4 ± 14.5
<0.01
HR 1 min post (bpm)
123.9 ± 20.7
139.6 ± 20.1
<0.01
HRR1 (bpm)
16.8 ± 8.2
27.8 ± 7.1
<0.01
HRR1 (<16 bpm),
31 (53.4%)
6 (24.0%)
<0.01
Peak exercise HR < 80% of predicted, (%)
52 (89.6%)
2 (8.0%)
<0.01
CR
0.6 ± 0.2
0.9 ± 0.1
<0.01
CRI, (%)
52 (89.7%)
6 (24.0%)
<0.01
Peak Load (W)
65.1 ± 26.4
144.0 ± 45.4
<0.01
Peak VO2 (ml/min)
779.9 ± 265.2
1659.9 ± 381.8
<0.01
Peak VO2% pred
41.1 ± 11.8
83.9 ± 13.4
<0.01
Peak (L/min)
43.64 ± 16.3
63.1 ± 14.7
<0.01
Peak BF (breaths/min)
33.8 ± 7.1
35.5 ± 6.6
>0.05
Peak O2 pulse (ml/beat)
5.6 ± 1.9
10.1 ± 2.0
<0.01
VE/VCO2 slope
41.5 ± 10.3
28.63 ± 3.9
<0.01
, , versus controls using unpaired -test. Values are presented as means ± SD. IPAH = idiopathic pulmonary arterial hypertension; % pred = percent of predicted; = number; BMI = body mass index; PaO2 = partial arterial oxygen pressure; PaCO2 = partial arterial carbon dioxide pressure; PFT = pulmonary function test; FVC = forced vital capacity; FEV1 = forced expiratory volume in 1 second; FEF25 = forced expiratory flow at 25% of forced vital capacity; FEF50 = forced expiratory flow at 50% of forced vital capacity; FEF75 = forced expiratory flow at 75% of forced vital capacity; DLco = gas transfer index or diffusing capacity for carbon monoxide; CPET = cardiopulmonary exercise test; Peak VO2 = peak oxygen uptake; = minute ventilation; VCO2 = carbon dioxide output; BF = breath frequency; HR = heart rate; ΔHR = heart rate changes from rest to peak; HRR1 = heart rate recovery at 1 minute; CR = chronotropic reserve; CRI = chronotropic incompetence.
