Pre-hospital heparin use for ST-elevation myocardial infarction is safe and improves angiographic outcomes

AIMS

This study aims to evaluate if pre-hospital heparin administration by paramedics is safe and improves clinical outcomes.

METHODS AND RESULTS

Using the multicentre Victorian Cardiac Outcomes Registry, linked with state-wide ambulance records, we identified consecutive patients undergoing primary percutaneous coronary intervention for STEMI between January 2014 and December 2018. Information on thrombolysis in myocardial infarction (TIMI) flow at angiography was available in a subset of cases. Patients receiving pre-hospital heparin were compared to those who did not receive heparin. Findings at coronary angiography and 30-day clinical outcomes were compared between groups. Propensity-score matching was performed for risk adjustment. We identified a total of 4720 patients. Of these, 1967 patients had TIMI flow data available. Propensity-score matching in the entire cohort yielded 1373 matched pairs. In the matched cohort, there was no observed difference in 30-day mortality (no-heparin 3.5% vs. heparin 3.0%, P = 0.25), MACCE (no-heparin 7% vs. heparin 6.2%, P = 0.44), and major bleeding (no-heparin 1.9% vs. heparin 1.4%, P = 0.64) between groups. Propensity-score analysis amongst those with TIMI data produced 552 matched pairs. The proportion of cases with TIMI 0 or 1 flow in the infarct-related artery (IRA) was lower among those receiving pre-hospital heparin (66% vs. 76%, P < 0.001) compared to those who did not.

CONCLUSION 

In this multicentre, propensity-score matched study, the use of pre-hospital heparin by paramedics was safe and is associated with fewer occluded IRAs in patients presenting with STEMI.

COILUMICA: coil embolization of a coronary artery to pulmonary artery fistula via novel dual lumen micro catheter technique

Background

Management of coronary artery fistula (CAF) is based on obliterating the fistula communication between the cardiac arteries and other thoracic vessels.

Case presentation

We describe the presentation of an 85-year-old female with progressive exertional dyspnea on a background of a long standing left anterior descending diagonal to pulmonary artery fistula. We utilized neuro-interventional techniques to perform coil embolization via use of a Scepter XC dual lumen micro catheter.

Conclusions

Dual lumen balloon catheters allow for super-selective artery interrogation, stability of balloon positioning, with less trauma to vessel architecture and accurate embolization. There were no complications and the patient reported improvement of symptoms on review.

"Liver or Let Die": Percutaneous PFO Closure Through Hepatic Vein Access

A 73-year-old farmer presented with platypnoea-orthodeoxia syndrome (POS). A transoesophageal echocardiogram (TOE) disclosed a patent foramen ovale (PFO) with significant right-to-left shunt on assuming upright posture. An initial attempt at PFO closure through the femoral vein was abandoned due to a completely occluded inferior vena cava. A second attempt through the internal jugular vein was also unsuccessful due to the steep angulation between superior vena cava and septum primum flap. Because of disabling symptoms, an attempt through a hepatic vein (HV) was scheduled and performed under general anaesthesia with TOE guidance. Ultrasound-guided access through an intercostal window to a peripheral HV was performed and the position confirmed with contrast injections. The PFO was easily crossed with a glide wire which was exchanged to a stiffer guide wire. A 25mm closure device was successfully deployed across the PFO. After retrieval of the delivery system, haemostasis of the HV was attained with a contrast-guided Gelfoam (Pfizer, New York, NY, USA) injection. Unfortunately, the patient had to undergo subsequent emergency coiling to an iatrogenically injured hepatic artery branch leading to full recovery and significant clinical improvement. Subsequent echocardiography demonstrated a well-positioned device with no residual shunt. This case illustrates that percutaneous PFO closure through a HV is a feasible procedure and should be considered in anatomy that is otherwise prohibitive for conventional approach. Extra care should be taken with initial vascular access into the HV and final haemostasis of the access site.

Threading the Eye of the Needle: A Challenging Case of Iatrogenic Spiral Coronary Artery Dissection

Catheter induced coronary dissection is an uncommon but potentially catastrophic complication of coronary angiography. We report a case of a 48-year-old female with normal coronary arteries on angiography complicated by extensive catheter induced spiral dissection. Wiring into the true lumen was a formidable challenge as a consequence of the large false lumen obliterating the true lumen. We present management strategies and in particular, highlight the important role of intravascular ultrasound (IVUS) imaging.

Patent foramen ovale and cryptogenic cerebral infarction

The patent foramen ovale (PFO) has been increasingly implicated in the aetiology of stroke, particularly in young patients with no other identifiable cause (cryptogenic stroke). The mechanism is by the passage of venous clots through the patent foramen into the arterial circulation, enabling cerebral embolism. Such patients with cryptogenic stroke and PFO are often treated with life-long anticoagulants or antiplatelet agents in an attempt to decrease the risk of a recurrence. Less commonly, surgical closure of the PFO has been undertaken in these patients. However, the recent evolution of closure devices that are delivered percutaneously by standard cardiac catheter techniques now offer an alternative non-surgical option. These alternative therapies are yet to be compared adequately. Two issues remain to be resolved. First, in determining appropriate therapy, patients with cryptogenic stroke may be divided into three groups: those with no PFO but an alternative unrecognized aetiology, those with an 'innocent' PFO and an alternative unrecognized aetiology and those with a causative PFO. The distinction between these groups clearly has important treatment implications. Second, the risk versus benefit of each available treatment modality must be determined for these different patient subgroups. These two issues require resolution before rational evidence-based treatment can be prescribed for patients with PFO and cryptogenic stroke.