Impact of catheter sizes and intracoronary glyceryl trinitrate on the TIMI frame count when digital angiograms are acquired at lower frame rates during elective angiography and PCI

Slow Coronary Flow: Pathophysiology, Clinical Implications, and Therapeutic Management

Coronary slow flow (CSF) is an angiographic phenomenon with specific epidemiologic characteristics, associated clinical presentation, and prognosis. Although patients with CSF are diagnosed as having "normal coronary arteries," it seems appropriate to consider CSF as a distinct disease entity requiring specific treatment. The patient with CSF is usually male, smoker, obese, with a constellation of risk factors suggestive of metabolic syndrome. Unstable angina is the most common clinical presentation, with recurrent episodes of chest pain at rest associated with electrocardiographic changes often requiring readmission and reevaluation. Regarding definition and diagnosis, interventionists should first exclude possible "secondary" causes of CSF, use objective means for definition and then differentiate from other similar conditions such as microvascular angina. Although the phenomenon is generally benign, patients with CSF are severely symptomatic with recurrent episodes of chest pain and poor quality of life. Furthermore, acute presentation of the phenomenon is commonly life-threatening with ventricular tachyarrhythmias, conduction abnormalities, or cardiogenic shock. Acute treatment of CSF includes, but is not restricted to, intracoronary infusion of dipyridamole, adenosine, or atropine. Chronic management of patients with CSF encompasses dipyridamole, diltiazem, nebivolol, telmisartan, and/or atorvastatin associated with amelioration of angina symptoms, improved quality of life, and good prognosis.

Safety and efficacy of femoral artery closure with the FemoSeal® device after coronary angiography using a 7 French sheath

Post-cardiac catheterization femoral artery hemostasis can be accomplished with several mechanisms, including the FemoSeal® hemostasis device which has been designed and approved for closure of 6 French (F) arterial puncture sites. The aim of this study was to investigate whether the FemoSeal® vascular closure device can effectively and safely seal 7F arterial puncture sites after diagnostic and interventional cardiac catheterizations.

Femoral artery puncture sites of 50 consecutive patients undergoing cardiac catheterization were closed with the FemoSeal® vascular closure device, according to the manufacturer’s instructions. Efficacy endpoints were time to hemostasis and successful ambulation. Safety endpoints included bleeding complications, vessel occlusion and pseudoaneurysms.

Mean time to hemostasis was 57.8±26.3 seconds (0-125 seconds). Hemostasis was achieved in 100 percent of the 50 patients. One patient suffered minor bleeding the next day, i.e. local hematoma.

This clinical study demonstrates that the FemoSeal® vascular closure device, initially approved for closure of 6F arterial puncture sites, shows promising efficacy and safety to seal a larger (7F) femoral arterial puncture sites after diagnostic and interventional cardiac catheterizations.

Impact of dye injection on intracoronary pressure

AIMS

Coronary angiography is widely used to estimate coronary blood flow velocity, as in the TIMI frame count method. However, it is unknown to what extent the injection of dye elevates intracoronary pressure which may accelerate coronary blood flow velocity. In the present study, intracoronary pressure was measured during coronary angiography.

METHODS AND RESULTS

In 25 patients with non-significant coronary lesions, assessed by fractional flow reserve measurement with a pressure guidewire, we recorded intracoronary pressure during dye injection for coronary angiography in the ostium of the coronary artery as well as distal to the lesion. There was a rise in mean intracoronary pressure during dye injection in both ostial and distal coronary arterial segments (from 90.8 +/- 17.2 mmHg to 96.8 +/- 18.5 mmHg and from 89.7 +/- 15.3 mmHg to 93.6 +/- 17.3 mmHg, respectively; p<0.001). Nevertheless, the absolute and relative increase in pressure was small (6.0 +/- 4.2 mmHg [6.7 +/- 4.9%] in the ostium, and 3.9 +/- 5.5 mmHg [4.2 +/- 5.7%] distally).

CONCLUSIONS

In coronary arteries without significant stenosis, coronary angiography causes only a minor increase in intracoronary pressure. The limited impact of dye injection on intracoronary blood pressure confirms the value of coronary angiography for estimation of coronary flow velocity.

Use of the TIMI frame count in the assessment of coronary artery blood flow and microvascular function over the past 15 years

Since its introduction, the TIMI frame count method has contributed to the understanding of the pathophysiology of coronary artery disease. In this article, the evolution of the TFC method and its applicability in the assessment of various therapeutic modalities are described.