Exhaustion of coronary vasodilatory reserve in the resting state: Clinical characteristics and long-term outcomes after intervention.

OBJECTIVES/BACKGROUND: Resting coronary blood flow approximates flow with maximal vasodilation in very severe coronary stenosis. We studied the incidence of exhausted vasodilatory reserve by FFR, its clinical characteristics and long-term prognosis after FFR guided percutaneous coronary intervention (PCI). METHODS: Consecutive patients undergoing FFR-guided PCI for coronary stenosis with reduced resting blood flow (baseline Pd/Pa < 0.8) were included. Basal maximal vasodilation (BMV) was defined as less than 5% difference between resting Pd/Pa and FFR, that is, FFR-baseline Pd/Pa < 0.05. RESULTS: Of 658 vessels that underwent FFR-guided PCI in 602 patients, 151 vessels had resting blood flow in the ischemic range (baseline Pd/Pa ≤ 0.8) and were included in the analysis. Of these, 28 lesions in 28 patients met criteria for BMV (4.25% of the entire registry and 18.5% of those with the reduced basal coronary flow). Stenosis severity was a significant predictor of the presence of BMV. In long term follow-up (median 106 ± 3.6 months), BMV was not associated with increased target vessel revascularization (TVR) or major adverse cardiac event compared to non-BMV(OR 1.9, 95% CI 0.7-4.8, p-value 0.2 and OR 1.3, 95% CI 0.75-2.5, p = 0.3, respectively). CONCLUSION: Low baseline Pd/Pa that approximates fractional flow reserve (exhausted vasodilatory reserve) defines a subgroup of patients with severe coronary artery stenosis. Prognosis, when treated with PCI along with medical therapy, appears similar to those with intact vasodilatory reserve.

Supraventricular tachycardia of the sick, a unique entity.

OBJECTIVE: This study explored a unique form of atrioventricular nodal reentrant tachycardia (AVNRT) in which certain acutely ill patients have a first episode of supraventricular tachycardia (SVT) with a short RP interval. METHODS: A retrospective chart review was conducted of patients at a single institution who developed SVT with short RP and yielded 19 patients. RESULTS: None of the 19 patients had a prior history of AVNRT or any other arrhythmia. The mean age was 58 years, the majority of patients were male (13/19), and there was a presence of hypertension (10/19), diabetes mellitus (5/19), hyperlipidemia (7/19), congestive heart failure (2/19), coronary artery disease (3/19), obstructive sleep apnea (2/19), and active cancer (8/19). The reasons for admission were planned surgery (8/19), sepsis (8/19), drug abuse (2/19), and neurological disorder (2/19). The AVNRT either terminated spontaneously or following the administration of adenosine. The patients were treated with amiodarone (12/19), metoprolol (6/19), or diltiazem (1/19). Follow-up (mean: 370 days) details revealed that patients were on amiodarone (3/19), metoprolol (6/19), were not taking any cardiac medication (5/19), or had passed away (5/19). Only 1 patient had a recurrence of AVNRT, and none of the patients required ablation therapy. CONCLUSION: 'AVNRT of the sick' has not been previously described in the medical literature, to our knowledge. It can be successfully treated with medications and the chance of recurrence after resolution of the acute illness is small.

ST Segment Elevation and Depressions in Supraventricular Tachycardia without Coronary Artery Disease.

ST segment changes are well documented in literature during supraventricular tachycardias. We present a case of a 21-year-old male who presents with chest pain, shortness of breath, and dizziness with an ECG showing atrioventricular reentrant tachycardia and diffuse ST segment depressions. Patient spontaneously converted to sinus rhythm, but he was still complaining of crushing chest pain. ECG taken after conversion showed sinus rhythm at a rate of 65 and showed obvious persistence of ST depressions in majority of leads. Emergent left heart catheterization showed normal coronaries. Such ST depression is suggestive of global ischemia in small intracardiac vessels that cannot be evaluated by left heart catheterization.

Acral gangrene as a presentation of non-uremic calciphylaxis.

We are describing a case of 55-year-old obese female with significant history of uncontrolled rheumatoid arthritis, who recently had decreased her immune-suppression medications. She presented with extensive acral gangrene involving multiple fingers and toes. Clinical picture and laboratory findings were suggestive of vasculitis; however, skin biopsy established diagnosis of calciphylaxis, in settings of normal kidney function. Patient was treated with sodium thiosulfate with gradual improvement in her skin lesions.