iEL~ .? -S
Do
EDITORIAL
we need the cardiologist
in the
prehospital triage for
STEMI? The objective of early therapy for acute myocardial infarction is restoration
of coronary flow as soon and as completely as possible. Bolus fibrinolytic agents are easy to administer, which has advantages in prehospital thrombolysis and in primary care centres. However, large clinical trials (INJECT,' GUSTO-III,2 and ASSENT-23) have not shown significant net clinical benefit over standard thrombolytic regimens. Yet, prehospital triage and thrombolysis has been shown to reduce time to treatment by about 60 minutes and consistently leads to a better outcome.4 Although lytic therapy for acute myocardial infarction is very widely applicable, it is only successful in restoring full early patency in about 50% of patients and has a low, but significant risk of severe side effects. Many feel that currently the optimum of coronary patency with bolus lytics has been achieved.5 Primary percutaneous transluminal coronary angioplasty (PTCA) carried out as an alternative to thrombolysis circumvents the cost and risk of thrombolytic therapy and restores patency in nearly 90% of cases. Data from randomised trials of primary PTCA vs. thrombolytic therapy in acute myocardial infarction are convincing.6 In the same way that primary thrombolysis has improved, also primary angioplasty seems even more successful using new preangioplasty drugs: full-dose thrombolysis,7 low-dose thrombolysis8 or glycoprotein receptor IIb/IIIa antagonists.9 This approach is currently called 'facilitated angioplasty'. As primary angioplasty proves to be a valuable and more effective alternative to thrombolysis, one should realise that acute angioplasty is expensive, needs a costly infrastructure and, therefore, is not widely applicable. Transport to a tertiary centre for primary angioplasty, however, seems feasible and safe. Although it delays time to treatment by a further 60 minutes, it tends to save lives and strokes and significantly reduces
reinfarction.'0
A.A. s,00 .
vF
T. Ta F.1 .
q C
,_
.....
..$..
i:t''
;
Primary angioplasty has been compared with prehospital thrombolytic therapy in only one large study, in the over 800 patients of the French CAPTIM trial." Interestingly, the gained time to treatment by prehospital therapy resulted in a similar outcome to primary angioplasty. Rescue procedures within 24 hours had to be done in about 30% ofpatients initially treated with prehospital lytic therapy. These results support prehospital triage and thrombolysis and transport to a tertiary centre, where early angioplasty can be performed if clinically indicated. Prehospital triage is usually carried out by ambulance doctors or ambulance nurses. Besides history, the first ECG is of utmost importance for a proper diagnosis before reperfusion therapy can be initiated. Although telephonic transmission of ECG is feasible and rapid, it costs time to alert a physician familiar with ECG reading, usually a cardiologist. Computer diagnosis is very reliable'2 and may circumvent the time-consuming consultation of a cardiologist. In this issue ofthe Netherlands HeartJournal cardiologists from Venlo report on the time to treatment of 151 patients with STEMI triaged by ambulance paramedics.'3 The median symptom to prehospital fibrinolytic treatment was well within two hours. ECG diagnosis was computerised
Netherlands Heart Journal, Volume 13, Number 9, September 2005
293
Editorial
:'~ .,a-t'
and telephone consultation with the cardiologist was only needed in 20% of cases. Rescue PCI was done in 41% of cases. Needless to say the 30-day outcomes were excellent: 5% mortality and 2% strokes. The prehospital approach can further be improved by rapid and reliable ECG diagnosis without further consultation at a distance. Furthermore, current ECG equipment can estimate the area at risk and, thus, advise the w * ~ ~ ~ ~ ~ ~ ~ ~ . . . . ;-. . . ij. . . ... paramedics on the optimal treatment: prehospital lysis (for smaller MIs) or transport for primary angioplasty (for large MIs). This has now been implemented in the national ambulance guideline. This approach in STEMI may, thus, result in prehospital lysis for smaller MIs or direct transport to a PCI centre after notification of the cath lab. With this strategy, delay in a non-PCI centre can be prevented, which is very effective in reducing time to PCI.14 Whether these patients need additional facilitation is currently being studied in large-scale trials. = .~~~~~~~~~~~~~~~~~~~~............ Thus, optimal early management of ST-elevation acute myocardial infarction is early restoration of coronary blood flow. Bolus TNK-tPA with heparin is the best pharmacological option. Yet, primary angioplasty seems ._ .. * :-'" .'~~~~~~~~~~~~~~~........ superior to thrombolysis in large MIs, even after transportation to a tertiary centre. Both strategies can be accomplished by prehospital triage with computerised ECG and subsequent treatment, for which consultation of a cardiologist seems redundant and certainly time consuming." U *.is
...e
'' Pi' ----''....
j|ijja L;ji
-.:: :**-,- ..
E-mail:[email protected]
Refrences 1 International Joint Efficacy Comparison ofThrombolytics. Randomised, double blind com2
,
, ...'. .. *~~~~~~~~~~~~~~~~~~~~~~..
3 4
5 ......
:
..........
*~~~~~~~~~~~~~~~~'
-
6 7
......
8
9 10 11
12
13 14
15
294
parison of reteplase double bolus administration with streptokinase in acute myocardial infarction (INJECT): trial to investigate equivalence. Lancet 1995;349:329-36. GUSTO-III Investigators. A comparison of reteplase with alteplase for acute myocardial infarction. NEnglJMcd 1997;337:1118-23. ASSENT-2 Steering Committee. Single bolus tenecteplase compared with front-loaded alteplase in acute myocardial infarction: the ASSENT-2 randomised trial. Lancet 1999;354: 1716-22. Morrison LJ, Verbeek PR, McDonald AC, Sawadsky BV, Cook DJ. Mortality and prehospital thrombolysis for acute myocardial infarction. JAMA 2000;283:2686-92. Verheugt FWA. GUSTO-V, the bottom line in fibrinolytic reperfusion therapy. Lancet 2001;357:1899-900. Keeley EC, Boura JA, Grines CL. Primary coronary angioplasty versus intravenous fibrinolytic therapy for acute myocardial infarction: a quantitative review of 23 randomised trials. Lancct 2003;361:13-20. Aviles FF, Alonso JJ, Castro-Beiras A, Vazquez N, Blanco J, Alonso-Briales, et al. Prospective randomized trial comparing a routine invasive strategywithin 24 hours to thrombolysis versus an ischemia-guided conservative approach to acute myocardial infarction with ST-segment elevation: the GRACIA-1 trial. Lancet2004;364:1045-53. Ross AM, Coyne KS, Reiner JS, et al. A randomized trial comparing primary angioplasty with a strategy of short-acting thrombolysis and immediate planned rescue angioplasty in acute myocardial infarction: the PACT trial. JAm Coll Cardiol 1999;34:1954-62. Topol EJ, Neumann FJ, Montalescot G. Apreferred reperfusion therapy for acute myocardial infarction. JAm Col Cardiol2003;42:1886-9. Pedersen F, Krusell LR, Abildgaard U, et al. A comparison of coronary angioplasty with fibrinolytic therapy in acute myocardial infarction. NEnglJMcd 2003;349:733-42. Bonnefoy E, Lapostolle F, Leizorovicz A, et al. Primary angioplasty versus prehospital fibrinolysis in acute myocardial infarction. Lancet2002;360:825-9. Lamfers EJP, Hooghoudt TEH, Uppelschoten A, Stolwijk PWJ, Boersma E, Simoons ML, et al. Prehospital versus hospital fibrinolytic therapy using automated versus cardiologist ECG diagnosis of myocardial infarction: abortion of myocardial infarction and unjustified fibrinolytic therapy. Am HeartJ2004;147:509-15. Firanescu C, WiTbers R, Meeder JG. Safety and feasibility ofprehospital thrombolysis in combination with active rescue PCI strategy for acute ST-elevation myocardial infarction. Neth HeartJ2005;13:300-4. Terkelsen GJ, Lassen JF, Norgaard BL, et al. Reduction of treatment delay in patients with ST-elevation myocardial infarction: impact of prehospital diagnosis and direct referral to primary percutaneous coronary intervention. EurHeartJ2005;26:770-7. Welsh RC, Chang W, Goldstein P, Adgey J, Granger GB, Verheugt FWA, et al. Time to treatment and the impact of a physician on prehopsital management of acute ST-elevation myocardial infarction: insights from the ASSENT-3 PLUS trial. Heart2005 (in press).
Nathcrbands Heart Journal, Volume 13, Number 9, Septenber 2005
a
Do
EDITORIAL
we need the cardiologist
in the
prehospital triage for
STEMI? The objective of early therapy for acute myocardial infarction is restoration
of coronary flow as soon and as completely as possible. Bolus fibrinolytic agents are easy to administer, which has advantages in prehospital thrombolysis and in primary care centres. However, large clinical trials (INJECT,' GUSTO-III,2 and ASSENT-23) have not shown significant net clinical benefit over standard thrombolytic regimens. Yet, prehospital triage and thrombolysis has been shown to reduce time to treatment by about 60 minutes and consistently leads to a better outcome.4 Although lytic therapy for acute myocardial infarction is very widely applicable, it is only successful in restoring full early patency in about 50% of patients and has a low, but significant risk of severe side effects. Many feel that currently the optimum of coronary patency with bolus lytics has been achieved.5 Primary percutaneous transluminal coronary angioplasty (PTCA) carried out as an alternative to thrombolysis circumvents the cost and risk of thrombolytic therapy and restores patency in nearly 90% of cases. Data from randomised trials of primary PTCA vs. thrombolytic therapy in acute myocardial infarction are convincing.6 In the same way that primary thrombolysis has improved, also primary angioplasty seems even more successful using new preangioplasty drugs: full-dose thrombolysis,7 low-dose thrombolysis8 or glycoprotein receptor IIb/IIIa antagonists.9 This approach is currently called 'facilitated angioplasty'. As primary angioplasty proves to be a valuable and more effective alternative to thrombolysis, one should realise that acute angioplasty is expensive, needs a costly infrastructure and, therefore, is not widely applicable. Transport to a tertiary centre for primary angioplasty, however, seems feasible and safe. Although it delays time to treatment by a further 60 minutes, it tends to save lives and strokes and significantly reduces
reinfarction.'0
A.A. s,00 .
vF
T. Ta F.1 .
q C
,_
.....
..$..
i:t''
;
Primary angioplasty has been compared with prehospital thrombolytic therapy in only one large study, in the over 800 patients of the French CAPTIM trial." Interestingly, the gained time to treatment by prehospital therapy resulted in a similar outcome to primary angioplasty. Rescue procedures within 24 hours had to be done in about 30% ofpatients initially treated with prehospital lytic therapy. These results support prehospital triage and thrombolysis and transport to a tertiary centre, where early angioplasty can be performed if clinically indicated. Prehospital triage is usually carried out by ambulance doctors or ambulance nurses. Besides history, the first ECG is of utmost importance for a proper diagnosis before reperfusion therapy can be initiated. Although telephonic transmission of ECG is feasible and rapid, it costs time to alert a physician familiar with ECG reading, usually a cardiologist. Computer diagnosis is very reliable'2 and may circumvent the time-consuming consultation of a cardiologist. In this issue ofthe Netherlands HeartJournal cardiologists from Venlo report on the time to treatment of 151 patients with STEMI triaged by ambulance paramedics.'3 The median symptom to prehospital fibrinolytic treatment was well within two hours. ECG diagnosis was computerised
Netherlands Heart Journal, Volume 13, Number 9, September 2005
293
Editorial
:'~ .,a-t'
and telephone consultation with the cardiologist was only needed in 20% of cases. Rescue PCI was done in 41% of cases. Needless to say the 30-day outcomes were excellent: 5% mortality and 2% strokes. The prehospital approach can further be improved by rapid and reliable ECG diagnosis without further consultation at a distance. Furthermore, current ECG equipment can estimate the area at risk and, thus, advise the w * ~ ~ ~ ~ ~ ~ ~ ~ . . . . ;-. . . ij. . . ... paramedics on the optimal treatment: prehospital lysis (for smaller MIs) or transport for primary angioplasty (for large MIs). This has now been implemented in the national ambulance guideline. This approach in STEMI may, thus, result in prehospital lysis for smaller MIs or direct transport to a PCI centre after notification of the cath lab. With this strategy, delay in a non-PCI centre can be prevented, which is very effective in reducing time to PCI.14 Whether these patients need additional facilitation is currently being studied in large-scale trials. = .~~~~~~~~~~~~~~~~~~~~............ Thus, optimal early management of ST-elevation acute myocardial infarction is early restoration of coronary blood flow. Bolus TNK-tPA with heparin is the best pharmacological option. Yet, primary angioplasty seems ._ .. * :-'" .'~~~~~~~~~~~~~~~........ superior to thrombolysis in large MIs, even after transportation to a tertiary centre. Both strategies can be accomplished by prehospital triage with computerised ECG and subsequent treatment, for which consultation of a cardiologist seems redundant and certainly time consuming." U *.is
...e
'' Pi' ----''....
j|ijja L;ji
-.:: :**-,- ..
E-mail:[email protected]
Refrences 1 International Joint Efficacy Comparison ofThrombolytics. Randomised, double blind com2
,
, ...'. .. *~~~~~~~~~~~~~~~~~~~~~~..
3 4
5 ......
:
..........
*~~~~~~~~~~~~~~~~'
-
6 7
......
8
9 10 11
12
13 14
15
294
parison of reteplase double bolus administration with streptokinase in acute myocardial infarction (INJECT): trial to investigate equivalence. Lancet 1995;349:329-36. GUSTO-III Investigators. A comparison of reteplase with alteplase for acute myocardial infarction. NEnglJMcd 1997;337:1118-23. ASSENT-2 Steering Committee. Single bolus tenecteplase compared with front-loaded alteplase in acute myocardial infarction: the ASSENT-2 randomised trial. Lancet 1999;354: 1716-22. Morrison LJ, Verbeek PR, McDonald AC, Sawadsky BV, Cook DJ. Mortality and prehospital thrombolysis for acute myocardial infarction. JAMA 2000;283:2686-92. Verheugt FWA. GUSTO-V, the bottom line in fibrinolytic reperfusion therapy. Lancet 2001;357:1899-900. Keeley EC, Boura JA, Grines CL. Primary coronary angioplasty versus intravenous fibrinolytic therapy for acute myocardial infarction: a quantitative review of 23 randomised trials. Lancct 2003;361:13-20. Aviles FF, Alonso JJ, Castro-Beiras A, Vazquez N, Blanco J, Alonso-Briales, et al. Prospective randomized trial comparing a routine invasive strategywithin 24 hours to thrombolysis versus an ischemia-guided conservative approach to acute myocardial infarction with ST-segment elevation: the GRACIA-1 trial. Lancet2004;364:1045-53. Ross AM, Coyne KS, Reiner JS, et al. A randomized trial comparing primary angioplasty with a strategy of short-acting thrombolysis and immediate planned rescue angioplasty in acute myocardial infarction: the PACT trial. JAm Coll Cardiol 1999;34:1954-62. Topol EJ, Neumann FJ, Montalescot G. Apreferred reperfusion therapy for acute myocardial infarction. JAm Col Cardiol2003;42:1886-9. Pedersen F, Krusell LR, Abildgaard U, et al. A comparison of coronary angioplasty with fibrinolytic therapy in acute myocardial infarction. NEnglJMcd 2003;349:733-42. Bonnefoy E, Lapostolle F, Leizorovicz A, et al. Primary angioplasty versus prehospital fibrinolysis in acute myocardial infarction. Lancet2002;360:825-9. Lamfers EJP, Hooghoudt TEH, Uppelschoten A, Stolwijk PWJ, Boersma E, Simoons ML, et al. Prehospital versus hospital fibrinolytic therapy using automated versus cardiologist ECG diagnosis of myocardial infarction: abortion of myocardial infarction and unjustified fibrinolytic therapy. Am HeartJ2004;147:509-15. Firanescu C, WiTbers R, Meeder JG. Safety and feasibility ofprehospital thrombolysis in combination with active rescue PCI strategy for acute ST-elevation myocardial infarction. Neth HeartJ2005;13:300-4. Terkelsen GJ, Lassen JF, Norgaard BL, et al. Reduction of treatment delay in patients with ST-elevation myocardial infarction: impact of prehospital diagnosis and direct referral to primary percutaneous coronary intervention. EurHeartJ2005;26:770-7. Welsh RC, Chang W, Goldstein P, Adgey J, Granger GB, Verheugt FWA, et al. Time to treatment and the impact of a physician on prehopsital management of acute ST-elevation myocardial infarction: insights from the ASSENT-3 PLUS trial. Heart2005 (in press).
Nathcrbands Heart Journal, Volume 13, Number 9, Septenber 2005
a
