Cardiol Res

Cardiology Research, ISSN 1923-2829 print, 1923-2837 online, Open Access

Article copyright, the authors; Journal compilation copyright, Cardiol Res and Elmer Press Inc

Journal website https://cr.elmerpub.com

Original Article

Volume 000, Number 000, November 2024, pages 000-000

Yield of Tilt Table Test in Diagnosing Syncope in Patients With Suspected Neurally Mediated Syncope

**Table 1.** Different Types of Response to Tilt-Testing
POTS: postural orthostatic tachycardia syndrome; VASIS: Vasovagal Syncope International Study.
Positive test	Changes in blood pressure and/or heart rate meeting the modified VASIS criteria with syncope, pre-syncope, orthostatic hypotension, or POTS and symptoms identical to clinical symptoms.
Negative test	Syncope, pre-syncope, orthostatic hypotension, or POTS are not provoked.
False-positive	Syncope, orthostatic hypotension, or POTS are provoked with symptoms different from clinical symptoms.
False-negative	Syncope, orthostatic hypotension, or POTS are not provoked in patients with solid clinical suspicion of neurally mediated syncope.

Table 1. Different Types of Response to Tilt-Testing

POTS: postural orthostatic tachycardia syndrome; VASIS: Vasovagal Syncope International Study.

Positive test

Changes in blood pressure and/or heart rate meeting the modified VASIS criteria with syncope, pre-syncope, orthostatic hypotension, or POTS and symptoms identical to clinical symptoms.

Negative test

Syncope, pre-syncope, orthostatic hypotension, or POTS are not provoked.

False-positive

Syncope, orthostatic hypotension, or POTS are provoked with symptoms different from clinical symptoms.

False-negative

Syncope, orthostatic hypotension, or POTS are not provoked in patients with solid clinical suspicion of neurally mediated syncope.

**Table 2.** The Patients’ Demographic Characteristics
	The patient’s total number (426), N (%)
SD: standard deviation; CV: cardiovascular.
Age, mean ± SD	38.40 ± 15.75 years
Gender
Male	212 (49.8.0%)
Female	214 (50.2%)
Clinical presentation
First episode of syncope	60 (14.1%)
Recurrent syncope	259 (60.8%)
Presyncope/dizziness	171 (25.1%)
CV risk factors/diseases
Diabetes mellitus	44 (10.3%)
Hypertension	76 (17.8%)
Dyslipidemia	38 (8.9%)
Ischemic heart disease	29 (6.8%)
Valve heart disease	40 (9.4%)
Heart failure	18 (4.2%)
Atrial fibrillation	15 (3.5%)
Ventricular tachycardia	4 (0.9%)
Congenital heart disease	36 (8.5%)

Table 2. The Patients’ Demographic Characteristics

The patient’s total number (426), N (%)

SD: standard deviation; CV: cardiovascular.

Age, mean ± SD

38.40 ± 15.75 years

Gender

Male

212 (49.8.0%)

Female

214 (50.2%)

Clinical presentation

First episode of syncope

60 (14.1%)

Recurrent syncope

259 (60.8%)

Presyncope/dizziness

171 (25.1%)

CV risk factors/diseases

Diabetes mellitus

44 (10.3%)

Hypertension

76 (17.8%)

Dyslipidemia

38 (8.9%)

Ischemic heart disease

29 (6.8%)

Valve heart disease

40 (9.4%)

Heart failure

18 (4.2%)

Atrial fibrillation

15 (3.5%)

Ventricular tachycardia

4 (0.9%)

Congenital heart disease

36 (8.5%)

**Table 3.** Tilt Table Test (TTT) Characteristics and Results
TTT	N/%
SD: standard deviation.
Degree of tilting
60	23 (5.4%)
70	333 (78.2%)
80	70 (16.4%)
Total test duration, mean ± SD	29.0 ± 15.397
Provocative test
Nitroglycerin (NTG)	181 (42.5%)
Isoproterenol	95 (22.3%)
None	150 (35.2%)
TTT results
Positive	295 (69.2%)
Negative	131 (30.8%)
False-negative	27 (6.3%)
False positive	11 (2.6%)
Neurally mediated syncope (NMS) type
Vasovagal	295 (69.2%)
Carotid sinus syndrome	2 (0.47%)
Situational syncope	2 (0.47%)
Psychogenic	8 (1.9%)
Postural orthostatic tachycardia syndrome (POTS)	10 (2.3%)

Table 3. Tilt Table Test (TTT) Characteristics and Results

TTT

N/%

SD: standard deviation.

Degree of tilting

23 (5.4%)

333 (78.2%)

70 (16.4%)

Total test duration, mean ± SD

29.0 ± 15.397

Provocative test

Nitroglycerin (NTG)

181 (42.5%)

Isoproterenol

95 (22.3%)

None

150 (35.2%)

TTT results

Positive

295 (69.2%)

Negative

131 (30.8%)

False-negative

27 (6.3%)

False positive

11 (2.6%)

Neurally mediated syncope (NMS) type

Vasovagal

295 (69.2%)

Carotid sinus syndrome

2 (0.47%)

Situational syncope

2 (0.47%)

Psychogenic

8 (1.9%)

Postural orthostatic tachycardia syndrome (POTS)

10 (2.3%)

**Table 4.** Comparison Between Nitroglycerin and Isoproterenol Protocols
	Nitroglycerin (n = 181, 42.5%)	Isoproterenol (n = 95, 22.3%)	P value
SD: standard deviation.
Age, mean ± SD	35.7 ± 16.5	30.1 ± 18.4	0.0001
Gender
Male	94 (51.9%)	52 (54.7%)	0.1939
Female	87 (48.1%)	43 (45.3%)
Syncope
First episode	29 (16.0%)	16 (16.8%)	0.1850
Recurrent	113 (62.4%)	48 (50.5%)	0.0600
Presyncope/dizziness	112 (61.9%)	66 (69.5%)	0.3670
Tilt table test
Total test time duration, mean ± SD	27.7 ± 6.5	46.9 ± 12.4	0.0001
Tilt table test result
Positive	140 (77.4%)	30 (31.6%)	0.0001
Negative	41 (22.7%)	65 (68.4%)	0.0001
False-negative	8 (4.4%)	14 (14.7%)	0.0020
False-positive	9 (4.97%)	0 (0.0%)	0.0230

Table 4. Comparison Between Nitroglycerin and Isoproterenol Protocols

Nitroglycerin (n = 181, 42.5%)

Isoproterenol (n = 95, 22.3%)

P value

SD: standard deviation.

Age, mean ± SD

35.7 ± 16.5

30.1 ± 18.4

0.0001

Gender

Male

94 (51.9%)

52 (54.7%)

0.1939

Female

87 (48.1%)

43 (45.3%)

Syncope

First episode

29 (16.0%)

16 (16.8%)

0.1850

Recurrent

113 (62.4%)

48 (50.5%)

0.0600

Presyncope/dizziness

112 (61.9%)

66 (69.5%)

0.3670

Tilt table test

Total test time duration, mean ± SD

27.7 ± 6.5

46.9 ± 12.4

0.0001

Tilt table test result

Positive

140 (77.4%)

30 (31.6%)

0.0001

Negative

41 (22.7%)

65 (68.4%)

0.0001

False-negative

8 (4.4%)

14 (14.7%)

0.0020

False-positive

9 (4.97%)

0 (0.0%)

0.0230

**Table 5.** Tilt Table Test Sensitivity, Specificity, Positive and Negative Predictive Values, and Accuracy After Adjusting for Age Group and Gender
	Sensitivity	Specificity	PPV	NPV	Accuracy
NPV: negative predictive values; PPV positive predictive values.
Overall	91% (0.88, 0.94)	89% (0.84, 0.95)	96% (0.93, 0.98)	79% (0.72, 0.86)	91% (0.88, 0.93)
Provocative test
Isoproterenol	68% (0.54, 0.81)	100% (1, 1)	100% (1, 1)	78% (0.68, 0.88)	85% (-0.016, 0.050)
Nitroglycerin	94% (0.90, 0.98)	78% (0.66, 0.90)	94% (0.89, 0.97)	80% (0.68, 0.92)	91% (0.88, 0.93)
None	96% (0.92, 0.99)	87% (0.73, 1.01)	98% (0.94, 1.00)	80% (0.64, 0.95)	95% (-0.011, 0.033)
Age group
Age ≥18 years (adult patients)	92% (0.88, 0.95)	85% (0.77, 0.92)	94% (0.91, 0.97)	79% (0.70, 0.87)	90% (-0.014, 0.044)
Age < 18 years (pediatric patients)	95% (0.89, 0.99)	83% (0.72, 0.93)	90% (0.83, 0.96)	91% (0.82, 0.99)	91% (0.88, 0.93)
Gender
Male	92% (0.88, 0.96)	82% (0.72, 0.91)	92% (0.87, 0.96)	83% (0.73, 0.92)	89% (-0.014, 0.044)
Female	93% (0.88, 0.96)	87% (0.79, 0.95)	95% (0.90, 0.98)	83% (0.74, 0.92)	91% (0.88, 0.93)

Table 5. Tilt Table Test Sensitivity, Specificity, Positive and Negative Predictive Values, and Accuracy After Adjusting for Age Group and Gender

Sensitivity

Specificity

PPV

NPV

Accuracy

NPV: negative predictive values; PPV positive predictive values.

Overall

91% (0.88, 0.94)

89% (0.84, 0.95)

96% (0.93, 0.98)

79% (0.72, 0.86)

91% (0.88, 0.93)

Provocative test

Isoproterenol

68% (0.54, 0.81)

100% (1, 1)

78% (0.68, 0.88)

85% (-0.016, 0.050)

Nitroglycerin

94% (0.90, 0.98)

78% (0.66, 0.90)

94% (0.89, 0.97)

80% (0.68, 0.92)

91% (0.88, 0.93)

None

96% (0.92, 0.99)

87% (0.73, 1.01)

98% (0.94, 1.00)

80% (0.64, 0.95)

95% (-0.011, 0.033)

Age group

Age ≥18 years (adult patients)

92% (0.88, 0.95)

85% (0.77, 0.92)

94% (0.91, 0.97)

79% (0.70, 0.87)

90% (-0.014, 0.044)

Age < 18 years (pediatric patients)

95% (0.89, 0.99)

83% (0.72, 0.93)

90% (0.83, 0.96)

91% (0.82, 0.99)

91% (0.88, 0.93)

Gender

Male

92% (0.88, 0.96)

82% (0.72, 0.91)

92% (0.87, 0.96)

83% (0.73, 0.92)

89% (-0.014, 0.044)

Female

93% (0.88, 0.96)

87% (0.79, 0.95)

95% (0.90, 0.98)

83% (0.74, 0.92)

91% (0.88, 0.93)