[Acute coronary syndrome after insect bites: a systematic review of available literature]

BACKGROUND

Kounis syndrome is a hypersensitivity coronary disorder induced by exposure to several triggers; the most common are antibiotics, followed by insect bites.

METHODS

We reviewed the literature and identified 66 patients who experienced acute coronary syndrome after insect bites.

RESULTS

The median age was 51 years, and 19.0% were women and only 12% had a history of allergy. The most involved insects were bee and wasp (86%) and the most frequent clinical manifestations were chest pain and anaphylaxis (36% and 29%, respectively). ST-segment elevation was the most common electrocardiographic finding (>70%). There was a not negligible rate of complications (15%), with a possible increased arrhythmic burden in patients without significant coronary atherosclerosis.

CONCLUSIONS

Acute coronary syndrome after insect bites is not so rare and it could have serious complications, with a possible increased arrhythmic burden in patients without significant coronary atherosclerosis.

[Stent loss and successful retrieval with the loop snare technique]

A 79-year-old woman was admitted to our coronary care unit for non-ST-elevation myocardial infarction. Urgent left transradial coronary angiography showed mid-distal high-grade stenosis of the left circumflex coronary artery. During percutaneous coronary intervention, stent dislodgement from the balloon catheter occurred. Fortunately, the guidewire was left in place through the detached stent, but a loop snare failed to cross the proximal circumflex artery. A second wire was placed in parallel to the first one and the first wire was caught in the loop snare, which was pulled back and closed at the level of the stent. Then, we cautiously pulled the guiding catheter together with the stent as a whole unit out of the introducer.

Mitral anular plane excursion predicts coronary stenosis during stress echocardiography with dipyridamole

Funding Acknowledgements

Type of funding sources: None.

Background

Dipyridamole stress echocardiography (DSE) is an important tool for detecting reversible ischemia in patients with suspected coronary artery disease (CAD); nonetheless, the results of the test are related to wall motion abnormalities, moderately operator-dependent, and left anterior descending (LAD) artery reserve, resulting in a moderate sensibility and specificity. 

Purpose

Aim Of our study was to evaluate whether an easy-to-use parameter like mitral annular plane systolic excursion (MAPSE) could be useful to identify CAD during DSE. 

Methods

We prospectively enrolled 512 patients that underwent DSE for suspected CAD; rest and peak MAPSE was acquired; 148 patients were referred to perform coronary angiography, with evidence of severe coronary stenosis in 91 patients.  

The mean age was 66.7 ±11 years, male gender was prevalent (64%). 

MAPSE at the peak was significantly different between patients with CAD and patient without (13,4mm vs 16,81 mm , p < 0.001); in fact, patients with CAD showed a blunted or no increase of MAPSE after dipyridamole infusion, with a significative difference in Delta Mapse (Mapse peak-Mapse rest) between groups ( -0.5mm vs 2.8mm) By using a Receiver Operating Curve, the Area under the curve was 0,764 (0.682-0.846), with the best cut-off value of +0.5mm (Sensibility 77%, Specificity 62% - Figure 1), comparabale with traditional methods like LAD reserve, FE reduction or Wall Motion Score Index. 

Discussion

to our knowledge, this is the first study that compared the behavior of MAPSE during dipyridamole infusion in patients with and without coronary artery disease. MAPSE is a well-known surrogate of longitudinal systolic function and has increased sensitivity over traditional methods of systolic performance such as LV-EF: in this context, dipyridamole induced reversible ischemia could affect prematurely MAPSE then EF or wall motion abnormalities.

In our study, in patients with evidence of reversible ischemia during DSE, a blunted or no increase of MAPSE was able to predict CAD. Incorporating this easy-to-use parameter could improve the specificity of DSE and strengthen the suspect of reversible ischemia when clear wall motion abnormalities are not found.

Abstract Figure. Mean value of Mapse and ROC curve

Speckle-tracking during dipyridamole stress echocardiography in the detection of myocardial ischemia in patients with suspected coronary artery disease

Background

The aim of this study was to investigate the incremental value of global longitudinal strain (GLS), postsystolic strain index (PSI) and prestretch (PSE) by automated function imaging with respect to wall motion (WM) and coronary flow reserve (CFR) for the diagnosis of significant coronary artery disease (CAD) during dipyridamole stress echocardiography.

Methods

We retrospectibely enrolled 227 patients with known or suspected CAD, approaching our echo lab to perform a DSE; all patient underwent coronary angiography within 1 month for clinical reasons. Obstructive CAD was defined as the evidence of >70% stenosis during coronary angiogram. Obstructive CAD was detected in 143 (63%) patients, while 84 (37%) had no significant CAD.

Global longitudinal strain, PSI and PSE were measured at rest and peak of the stress (after 6 minutes of 0,84mg/kg of dipyridamole infusion).

Results

Patient with CAD showed a significantly lower GLS at rest (−16.9±4.2 vs −18.6±3.4; p<0.01) and peak (14.9±3.8 vs −21.50±3.3; p<0.01) Figure A; the behavior of GLS was opposite, in patient with CAD showed an increase while in patient without CAD a significant decrease after dipyridamole infusion. There was also a significant difference between groups for Delta PSI (PSIpeak − PSIrest) and Delta PSE (PSEpeak − PSErest), respectively 126±145 vs −40±97, (p<0.01) and 108±163 vs −41±106 (p<0.01) Figure C. ROC analyses produced a statistically valid model: Average GLS at peak (p 0.001; AUC=0.906, cut-off value −18%, sensitivity 83% and specificity 82%); on the basis of these results, we compared WM and myocardial deformation analysis and GLS was superior to CFR LAD, Delta EF, Delta ESV and Delta WMI (Figure B).

Conclusions

GLS, PSE and PSI show an opposite response to dipyridamole, in patients with CAD in patient without CAD and show much higher sensitivity and specificity compared to the conventional parameters like WMI, EF and CFR in detecting CAD

Funding Acknowledgement

Type of funding source: None

Time course of effects of cardiac resynchronization therapy in chronic heart failure: benefits in patients with preserved exercise capacity

OBJECTIVES

To assess in patients with chronic heart failure the effect of cardiac resynchronization therapy (CRT) over 12 months' follow-up the time course of the changes in functional and neurohormonal indices and to identify responders to CRT.

METHODS

Eighty-nine patients (74.1 +/- 1 years, left ventricular ejection fraction [LVEF] < 35%), QRS complex duration >150 ms, in stable New York Heart Association (NYHA) class III or IV on optimal medical treatment were prospectively randomized either in a control (n = 45) or CRT (n = 44) group and underwent clinical evaluation, cardiopulmonary exercise testing (CPET), 2D-Echo, heart rate variability (HRV), carotid baroreflex (BRS), and BNP assessments before and at 6- and 12-month follow-up.

RESULTS

In the CRT group, improvement of cardiac indices and BNP concentration were evident at medium term (over 6 months) follow-up, and these changes persisted on a longer term (12 months) (all P < 0.05). Instead CPET indices and NYHA class improved after 12 months associated with restoration of HRV and BRS (all P < 0.05). We identified 26 responders to CRT according to changes in LVEF and diameters. Responders presented less depressed hemodynamic (LVEF 25 +/- 1.0 vs 22 +/- 0.1%), functional (peak VO(2) 10.2 +/- 0.2 vs 6.9 +/- 0.3 ml/kg/min), and neurohormonal indices (HRV 203.6 +/- 15.7 vs 147.6 +/- 10.ms, BRS 4.9 +/- 0.2 vs 3.6 +/- 0.3 ms/mmHg) (all P < 0.05). In the multivariate analysis, peak VO(2) was the strongest predictor of responders.

CONCLUSIONS

Improvement in functional status is associated with restoration of neurohormonal reflex control at medium term. Less depressed functional status (peak VO(2)) was the strongest predictor of responders to CRT.

[Prognostic value of supraventricular arrhythmias in heart failure]

Supraventricular tachyarrhythmias can be responsible for severe hemodynamic derangement which may contribute to the progression and worsening of heart failure. The resultant effect of these arrhythmias, however, is conditioned by several concomitant factors, such as age of the patients, left ventricular systolic function, and ventricular rate response. If the role of such arrhythmias in functional class, morbidity, and functional capacity is well accepted, controversial data are available on their role on mortality in patients with heart failure.

Effect of ursodeoxycholic acid on hypertransaminasaemia and bile acid composition in patients undergoing bone marrow transplantation--a double-blind randomized control study

A double-blind randomized placebo controlled trial of ursodeoxycholic acid was performed in 31 patients undergoing T-cell depleted allogeneic or autologous bone marrow transplantation to determine the effectiveness of this hydrophilic bile acid in improving the increase in serum liver enzymes that generally accompanies this procedure. Neither group showed any significant difference in magnitude of the increases in serum transaminases and gamma-glutamyltranspeptidase following the conditioning regimen that included chemotherapy and total body irradiation. In the 6 months after transplantation, serum enzymes decreased in both groups, but were consistently higher in the placebo treated patients, indicating that ursodeoxycholic enhances normalization of liver. Faecal bile acid showed that following chemotherapy and irradiation in which intestinal bacteria are ablated, secondary bile acid formation was practically abolished and faeces contained mainly cholic and chenodeoxycholic acids. During bile acid treatment, ursodeoxycholic acid accounted for 31.3 +/- 10.9% of faecal bile acids compared with 4.0 +/- 2.1% in the basal period. Serum and urinary ursodeoxycholic acid concentrations (mean +/- SD, 13.3 +/- 6.9 mumol/L and 2.65 +/- 0.84 mumol/L, respectively) were significantly higher in patients receiving bile acid than in thos on placebo (mean +/- SD, 0.15 +/- 0.12 mumol/L and 0.29 +/- 0.35 mumol/L, respectively) thus confirming compliance.

[The noninvasive identification of patients with angina and normal coronary arteries]

BACKGROUND

Although patients with syndrome X (angina and normal coronary arteries, in absence of coronary spasm, cardiomyopathy or valvulopathy) and those with stable angina as well as documented coronary artery disease share a similar clinical presentation (effort related symptoms, positive exercise stress testing and reversible perfusion defects), their prognosis is markedly different. Coronary atherosclerosis is usually progressive relative to morbidity and mortality. Conversely prognosis both in terms of persistence of pain and mortality appears to be benign in syndrome X. Most cardiologists favor proceeding with coronary angiography in all patients presenting with exercise induced ST depression and reversible perfusion defects. However, it should not be assumed that this strategy will remain the preferred one. The aim of this study was to assess whether non invasive testing could identify underlying coronary artery anatomy, thus prognosis in the above subset of patients. The approach was selected on a clearly stated objective of how isosorbide dinitrate and verapamil may influence coronary flow reserve, thus exercise stress testing in syndrome X. Nitrates have been shown to reduce coronary flow reserve during stress tachycardia. The opposite occurs with calcium blockers.

METHODS

We studied 48 patients with effort angina referred to our laboratory for diagnostic evaluation. All patients underwent two separate sessions at one-day interval. Each session consisted of exercise stress testing before and after isosorbide dinitrate (s.l.; 5-10 mg) or verapamil (i.v.; 10 mg), given in a randomized crossover fashion. Angiography was performed within 3 months from testing. Efficacy of drugs in terms of exercise capacity was assessed by using the following criteria: 1) prevention of significant (> or = 0.1 mV) ST depression while reaching same workload levels attained during baseline testing; 2) improvement in the ischemic thresholds, that is an increase in: time to 0.1 mV ST depression > or = 120 sec., with heart rate (> or = 10 bpm) and rate pressure product (> or = 2 U x 1000) greater than those attained during baseline testing; 3) increase in time to peak exercise (> or = 120 sec).

RESULTS

In syndrome X, both drugs resulted ineffective in one patient, one patient showed a favourable response to isosorbide dinitrate whereas the remaining 13/15 patients improved exercise capacity following verapamil, but not isosorbide dinitrate. The opposite occurred in coronary artery disease patients: both isosorbide dinitrate and verapamil were effective in 21/33 patients, and ineffective in 8/33 patients. The remaining 4 patients responded to isosorbide dinitrate but not to verapamil.

CONCLUSIONS

1) Verapamil, but not isosorbide dinitrate, improves exercise capacity in syndrome X; 2) this does not apply to patients with stable angina; 3) a favourable response to verapamil but not to isosorbide dinitrate is both a sensitive (86%) and specific (100%) method for identifying patients with angina and normal coronary arteries; 4) non invasive testing may select those effort angina patients who have to proceed directly to coronary angiography; 5) some patients with effort related angina may not require further investigation.

[Myocardial infarct with normal coronary vessels: an association with dysfunction of the coronary microcirculation]

The association of acute myocardial infarction (AMI) with normal coronary arteries was analyzed prospectively. A series of 128 consecutive patients underwent coronary angiography within 1 week from AMI. Seven patients, all females, had no coronary artery lesions and were considered eligible for the study. All 7 patients underwent atrial pacing (10 g/min increments every 2 min), ergonovine testing (E; total dose 0.650 mg i.v.). Great cardiac vein flow (GCVF; thermodilution technique), mean aortic pressure (MAP), anterior coronary resistance (ACR) and myocardial lactate extraction [(Lac art-Lac gcv)/Lac art] were measured at baseline and during testing. Pacing-induced typical chest pain occurred in 5 patients: 4 of them showed concurrent significant (> or = 0.15 mV) ST downsloping. At peak pacing, GCVF increased only by < 50%, or even decreased, in all patients. Baseline lactate extraction (0.13 +/- 0.11) changed to lactate production (-0.15 +/- 0.10) in 7/7 patients. None of the patients showed focal epicardial coronary artery spasm following E. During testing, however, all 7 patients showed decrease in GCVF (110 +/- 47 versus 74 +/- 21; p < 0.005), increase in ACR (0.92 +/- 0.29 versus 1.43 +/- 0.20; p < 0.001), and significant coronary lactate production (-0.18 +/- 0.12). Six patients referred slight to moderate chest pain, which was accompanied by ST downsloping in 4.(ABSTRACT TRUNCATED AT 250 WORDS)

Left ventricular dynamics after aortic valve replacement: a long-term, combined radionuclide angiographic and ultrasonographic study

Between January 1985 and July 1990, we studied 71 patients at our institution who underwent aortic valve replacement for either aortic valve regurgitation (40 patients) or stenosis (31 patients). The following prostheses were implanted: 25 St. Jude Medical valves (bileaflet), 16 Björk-Shiley (monoleaflet, tilting disc, 60 degrees convexo-concave), 16 Medtronic-Hall (monoleaflet, tilting disc), and 14 Starr-Edwards (caged ball). The patients were evaluated pre-and postoperatively by means of gated blood-pool scintigraphy and Doppler echocardiography. Postoperatively, each patient was studied at 6 months, 1 year, and then annually. The evaluations focused upon 1) scintigraphically assessed left ventricular performance indicators (end-diastolic and end-systolic volume, as well as resting and exercise ejection fraction) and 2) Doppler-derived hemodynamic indexes (peak and mean transvalvular pressure gradient, effective orifice area, regurgitant flow, and systolic wall stress). Early after aortic valve replacement, 55 (77.5%) of the patients had substantial symptomatic relief, with normal hemodynamic values both at rest and during exercise (New York Heart Association functional class I or II); another 6 patients (8.5%) maintained their preoperative status in those classes. Within a year after surgery, a majority of patients showed a significant reduction in left ventricular dimensions. The patients with preoperative aortic valve stenosis had a significantly reduced end-diastolic and end-systolic volume (p<0.05), a moderately reduced left ventricular mass index (p<0.01), and a significantly increased exercise ejection fraction (p<0.05); moreover, in all 31 of these cases, systolic wall stress returned to normal or lower-than-control values (p<0.005). The patients with preoperative aortic valve regurgitation had a significant reduction in end-diastolic and end-systolic volume (p<0.005), diastolic wall stress (p<0.005), and a significant increase in exercise ejection fraction (p<0.01); however, their left ventricular mass index was not significantly reduced. Optimal long-term survival was afforded by the St. Jude valve in the small size (21 mm) and the Starr-Edwards valve in the large size (27 mm). This study represents the first reported use of a serial, combined radionuclide and echocardiographic procedure for the follow-up of patients undergoing aortic valve replacement. During the 5(1/2)-year follow-up period, this combined technique proved highly accurate for collecting follow-up data, often complementing or correcting simple ultrasound results. This diagnostic approach enabled us to 1) obtain information comparable to or better than that provided by cardiac catheterization, 2) identify complications early, 3) differentiate between valvular and ventricular failure, and 4) suggest the valve of choice (not always that with the best hemodynamic performance) in patients with different cardiac variables. Further research is needed to confirm this study, the results of which could change many medical and surgical strategies for clinical management of the diseased aortic valve.