Reinfarction after Thrombolysis for STEMI

Problem Statement

• Reocclusion of infarct-related artery following successful fibrinolysis in STEMI remains a major limitation

• Is clinically silent in over 50 percent of cases

• Reocclusion can result in reinfarction in 3-5%of cases before hospital discharge & upto 25% cases within 3 months of primary procedure.

Definition

• Reinfarction is defined as acute MI that occurs

within 28 days of an incident or recurrent MI

• Consider reinfarction in the following situation:

– ST elevation >0.1 mV recurs, Or

– New pathognomonic Q waves appear, in at least two

contiguous leads, particularly when associated with

ischemic symptoms for 20 min or longer.

Type of Reinfarction

Type Etiology

Type 1 Spontaneous

Type 2 Secondary

Type 3 Sudden death

Type 4a PCI-related

Type 4b Stent-related

Type 5 CABG-related

Diagnosis

• Immediate measurement of cardiac tropinins is

done and a 2nd sample obtained 3-6 hrs later

• If the cTn concentration is elevated, but stable

or decreasing at the time of suspected

reinfarction, the diagnosis of reinfarction

requires a > 20% increase of the cTn value in

the second sample.

• If the initial cTn concentration is normal, the

criteria for new acute MI apply.

• In-hospital recurrent MI following fibrinolytic

administration is associated with an increased

risk of long-term mortality

• Mortality risk increases not only at 30-days but

also at 2 years compared to patients not

suffering from reinfarction

Kaplan-Meier survival curves for reinfarction patients

Gibson CM et al. J Am Coll Cardiol. 2003 Jul 2;42(1):7-16

Increased mortality at 30 days post reinfarction

Kaplan-Meier estimated mortality rates up to 2 years

Gibson CM et al. J Am Coll Cardiol. 2003 Jul 2;42(1):7-16

Higher mortality rates for reinfarction

Pathophysiology

Thrombin related mechanisms for reocclusion

Role of plasmin and fibrinolysis inhibitors in reocclusion

Treatment Strategies-Rethrombolyis or

Revascularization?

Management strategies for reinfarction in non-US centers in GUSTO I and ASSENT 2

Rethrombolysis favored by majority of non-USA hospitals

Clinical Outcome of Patients in GUSTO I trial by the 3 Treatment Groups

Barbash GI et al. Circulation. 2001;103:954-960

Clinical Outcome of Patients in the ASSENT 2, by the 3 Treatment Groups

Predictors of Reinfarction

Hudson MP et al. Circulation. 2001;104:1229-1235

Some predictors of reinfarction based on analysis of GUSTO I & GUSTO III Trials are:

• Advanced age

• Shorter symptom duration before fibrinolysis

• Nonsmoking status

Reinfarction associated with DES-related reocclusion

• Occurs with the use of Drug-eluting stents

• DES were originally developed to obviate the problem of endothelialization of stents

• The drugs included in the DES do prevent the ingrowth of cells.

• However, another problem associated with them is sudden occlusion by thrombus formation

• This sudden occlusion can lead to critical

stenosis and even reinfarction

• The only solution is to continue dual antiplatelet

therapy for atleast 1 year after DES implantation

• It has been observed that there is higher rate of

reocclusion if DAPT is discontinued before 1

year

• Thus reinfarction is not an uncommon

phenomenon after fibrinolytic therapy for MI

• Reinfarction is associated with significantly

increased mortality at 30-day and 2-years after

index MI

• Rethrombolytic therapy is associated with

increased chances of bleeding, esp intracranial

hemorrhage.

Thank You