Echocardiographic Screening for Pulmonary Hypertension in Stable COPD Out-Patients and NT-proBNP as a Rule-Out Test

Figures & data

Table 1.  Patient demographics

	All Pts (Total n = 117)	n	No PH (Total n = 97)	n	PH (Total n = 16)	n	P (PH vs No PH)
Age (years)	70 ± 1	117	69 ±1	97	75 ± 2 *	16	0.01
BMI (kg/m2)	25 ± 0.6	113	25 ± 1	93	25 ± 1	16	0.8
Female (% of pts)	61	117	64	97	50	16	0.3
Years since diagnosis (median (95% CI))	8 (5–10)	107	8 (5–10)	90	9 (5-12)	13	0.3
Pack-years	43 ± 3	109	43 ± 3	96	40 ± 6	15	0.7
Spirometry (% of expected)
FEV1	42 ± 2	116	43 ± 2	96	37 ± 4	16	0.2
FVC	72 ± 2	116	73 ± 2	96	63 ± 5*	16	0.04
COPD Class (% of pts)
Mild	2	117	2	97	0	16	0.6
Moderate	30	117	31	97	25	16	0.6
Severe	44	117	44	97	38	16	0.6
Very severe	25	117	23	97	38	16	0.2
COPD treatment (% of pts)
SABA	75	117	73	97	88	16	0.2
Ipratropium	17	117	16	97	25	16	0.4
LABA	86	117	86	97	88	16	0.8
Tiotropium	68	117	69	97	62	16	0.6
Inhaled glucocorticoids	86	117	85	97	94	16	0.3
Glucocorticoids p.o.	10	117	11	97	6	16	0.5
Theofylline	3	117	2	97	13*	16	0.03
Oxygen treatment	8	117	5	97	19 *	16	0.0495
Cardiovascular disease (% of pts)
Any cardiovascular disease	42	117	38	97	69*	16	0.02
Atrial fibrillation	10	117	7	97	31*	16	0.003
Ischemic heart disease	17	117	15	97	25	16	0.6
Former myocardial infarct	14	117	13	97	19	16	0.6
Left ventricular failure	6	117	5	97	13	16	0.25
Hypertension	35	116	34	96	50	16	0.2

Results are expressed as median with 95% CI, means ± SEM or proportions (e.g., 61% of patients were female). *p < 0.05 vs no PH. Total n indicates the number of patients in each group. n indicates the number of patients from whom data were available. Data for the 4 patients in which echocardiography was inconclusive are included in the data from all patients. No PH: No signs of PH on echocardiography. PH: patients screened positive by echocardiography. SABA: Short-acting β-adrenoceptor agonists, LABA: long-acting β-adrenoceptor agonists. Pts: Patients. Any cardiovascular disease describes the presence of one or more of the specific diseases listed.

Figure 1.  Mortality. Kaplan-Meier survival curves for patients without and with PH on echocardiography defined as a tricuspid regurgitation pressure gradient > 40 mmHg, a tricuspid annular plane systolic excursion < 1.8 cm or right ventricular dilatation. * p < 0.05 vs. no PH on echocardiography.

Table 2.  Six-minute walk test

	No PH (Total n = 97)	n	PH (Total n = 16)	n	P (PH vs No PH)
[spanname = “1to6”]6-minute walk test
Distance (m)	339 ± 15	88	224 ± 31 *	14	0.006
Saturation before (%)	94 ± 3	93	91 ± 2 *	15	0.01
Saturation after (%)	90 ± 0.6	88	87 ± 3	12	0.09
Borg score before	1.8 ± 0.2	85	3.5 ± 1.0 *	13	0.004
Borg score after	4.7 ± 0.3	82	5.5 ± 0.8	13	0.3

Results are expressed as mean ± SEM.*: p < 0.05 vs no PH. Total n indicates the number of patients in each group. n indicates the number of patients from whom data were available. No PH: No signs of PH on echocardiography. PH: patients screened positive by echocardiography.

Figure 2.  NT-proBNP as a first line screening tool. A: Receiver operator characteristics plot for NT-proBNP and the presence of PH on echocardiography. B: Dotplot of NT-proBNP in patients with and without PH on echocardiography. Dashed line indicates cut-off value used for calculation of sensitivity, specificity, positive and negative predictive values. Error bars indicate means ± SEM. * p<0.05 vs. no PH on echocardiography.