Systolic time intervals combined with Valsalva maneuver for the diagnosis of left ventricular dysfunction in COPD exacerbations

Figures & data

Table 1 Patients’ characteristics at admission

Characteristic	LVD group n=71	No LVD group n=95
Age, years, mean (SD)	67 (11)	60 (16)*
Sex (male/female)	43/34	59/18
Previous medical history, n (%)
Arterial hypertension	49 (63)	19 (24)*
Diabetes	32 (41)	14 (17)*
Coronary artery disease	13 (16)	3 (3)*
Systolic arterial pressure, mmHg, mean (SD)	154 (34)	147 (32)
Diastolic arterial pressure, mmHg, mean (SD)	86 (18)	84 (20)
Heart rate, beats/minutes, mean (SD)	91 (22)	98 (23)
Arterial blood gas
PaO2, mmHg, mean (SD)	74 (27)	70 (33)
PaCO2, mmHg, mean (SD)	38 (22)	45 (15)*
BNP serum level, pg/mL, median (IQR)	1,327 (370–2,283)	292 (195–390)*
Left ventricular ejection fraction %, mean (SD)	40 (9)	65 (14)*
Late to early diastolic Doppler velocity E/A ratio	1.33	1.06

Note:

* P<0.05 LVD vs non-LVD group.

Abbreviations: BNP, brain natriuretic peptide; IQR, interquartile range; LVD, left ventricular dysfunction; PaCO₂, partial pressure of carbon dioxide; PaO₂, partial pressure of oxygen; SD, standard deviation.

Table 2 Systolic time intervals at baseline and under Valsalva maneuver

Variables	LVD group n=71	No LVD group n=95	P-value
Baseline
EMAT ms, mean (SD)	114 (31)	93 (17)	<0.001
LVET ms, mean (SD)	304 (60)	402 (53)	<0.001
EMAT/LVET, mean (SD)	0.38 (0.1)	0.23 (0.06)	<0.001
Valsalva maneuver
EMATVM ms, mean (SD)	110 (32)	81 (26)*	<0.001
LVETVM ms, mean (SD)	294 (58)	391 (52)*	<0.001
EMATVM/LVETVM, mean (SD)	0.39 (0.1)	0.21 (0.08)*	<0.001

Note:

* P<0.05 compared to baseline.

Abbreviations: EMAT, electromechanical activation time; EMAT_vm, electromechanical activation time under Valsalva maneuver; LVD, left ventricular dysfunction; LVET, left ventricular ejection time; LVET_vm, left ventricular ejection time under Valsalva maneuver; SD, standard deviation.

Table 3 Diagnostic performance of systolic time intervals at baseline and under Valsalva maneuver

Variables	Area under ROC curve	(95% CI)	Correlation with BNP
			Coefficient	P-value
Baseline
EMAT	0.79	(0.71–0.87)	0.31	<0.001
LVET	0.88	(0.82–0.94)	0.49	<0.001
EMAT/LVET	0.90	(0.85–0.95)	0.51	<0.001
Valsalva maneuver
EMATVM	0.84	(0.76–0.92)	0.41	<0.001
LVETVM	0.88	(0.82–0.94)	0.48	<0.001
EMATVM/LVETVM	0.92	(0.87–0.97)	0.55	<0.001

Abbreviations: BNP, brain natriuretic peptide; CI, confidence interval; EMAT, electromechanical activation time; EMAT_vm, electromechanical activation time under Valsalva maneuver; LVET, left ventricular ejection time; LVET_vm, left ventricular ejection time under Valsalva maneuver; ROC, receiver operating characteristic.

Figure 1 Systolic time intervals in patients with and without left ventricular dysfunction, EMAT (A), LVET (B), and EMAT/LVET ratio (C).

Abbreviations: EMAT, electromechanical activation time; LVET, left ventricular ejection time; LVD, left ventricular dysfunction.