The cost implications of an early versus delayed invasive strategy in acute coronary syndromes: the TIMACS study

Figures & data

Table 1. Summary of the TIMACS trial at 6 months.

	Early Intervention (n = 1593)	Delayed Intervention (n = 1438)	Hazard Ratio (95% CI)
Clinical outcome
Primary outcome* (%)	9.6	11.3	0.85 (0.68–1.06)
Primary outcome (GRACE ≥140) (%)	13.9	21.0	0.65 (0.48–0.89)
Primary outcome (GRACE <140) (%)	7.6	6.7	1.12 (0.81–1.56)
Death (%)	4.8	5.9	0.81 (0.60–1.11)
New MI (%)	4.8	5.7	0.83 (0.61–1.14)
Stroke (%)	1.3	1.4	0.90 (0.49–1.68)
Refractory ischemia (%)	1.0	3.3	0.30 (0.17–0.54)
Rehospitalization for unstable angina (%)	1.0	0.9	1.12 (0.53–2.40)
Non-fatal cardiac arrest (%)	0.8	1.3	0.60 (0.29–1.25)
Heart failure (%)	5.3	5.7	0.93 (0.69–1.26)
Intervention
PCI (%)	60.1	55.8	1.37 (1.24–1.50)
Median time (hrs)	16	52
Interquartile range (hrs)	3–23	41–101
CABG (%)	16.2	15.5	1.07 (0.90–1.29)
Median time (days)	7.8	10.8
Interquartile range (days)	4.7–17.4	6.7–19.8
CABG + PCI (%)	1.6	1.8	0.90 (0.53–1.56)
Safety outcome
Major bleeding (%)	3.1	3.5	0.89 (0.60–1.31)
Duration in hospital
Index hospital stay (days) (median, IR)	7 (4–10)	8 (5–12)	N/A
Total hospital stay (days) (median, IR)	7 (5–14)	9 (6–15)	N/A

*Death, myocardial infarction, stroke at 6 months.

MI = myocardial infarction; PCI = percutaneous coronary intervention; CABG = coronary artery bypass grafting; IR = interquartile range; N/A = not applicable.

Table 2. Unit costs per DRG code.

DRG	DRG code	Medicare Cost (US$)
Cost per clinical event
MI	280–285	7083
Unstable angina	286–287	6001
Stroke	64–66	6051
Refractory ischemia	313	2290
Rehospitalization for unstable angina	286–287	6001
Non-fatal cardiac arrest	296–298	5246
Heart failure	291–293	5330
Coronary angiogram	250–251	10,101
PCI	246–249	10,888
CABG	233–234	27,362
CABG + PCI	231–232	36,425
Cost per hospital stay
Cost per day	N/A	869

DRG = diagnosis-related group; MI=myocardial infarction; PCI =  percutaneous coronary intervention; CABG = coronary artery bypass grafting; N/A = not applicable.

Table 3. Average costs (US$) per patient.

	Early Intervention	Delayed Intervention	Difference (95% CI)
Clinical Event Cost	7747	7943	−196 (−430, 38)
Procedural Cost	15,036	14,690	346 (−440, 1132)
Hospital Stay Cost	9871	11,191	−1320 (−2074, −566)
Total Cost	32,654	33,824	−1170 (−2542, 202)

Figure 1. Bootstrap results of TIMACS patients displayed in a cost–effectiveness plane.

Figure 2. Bootstrap results of high-risk GRACE patients displayed in a cost–effectiveness plane.

Table 4. Subgroup analysis of average cost (US$) per patient.

	Early Intervention	Delayed Intervention	Difference (95% CI)	p-interaction
Age
<65 yrs	30,359	32,063	−1704 (−3452, 44)	0.19
≥65 yr	34,471	35,052	−581 (−2545, 1383)
Sex
Female	31,863	32,597	−734 (−2927, 1459)	0.98
Male	33,107	34,473	−1366 (−3124, 392)
ST-segment deviation
No	31,568	32,468	−900 (−2740, 940)	0.34
Yes	33,706	35,257	−1551 (−3507, 405)
Elevated cardiac biomarker
No	32,769	32,691	78 (−2967, 3123)	0.20
Yes	32,622	34,145	−1523 (−3045, −1)
GRACE score
0–140	31,987	31,958	29 (−1554, 1612)	0.03
≥141	34,033	37,753	−3720 (−6270,−1170)