Intracoronary electrocardiogram detects coronary microvascular dysfunction and ischemia in patients with no obstructive coronary arteries disease.

BACKGROUND: Coronary microvascular dysfunction (CMD) is the leading cause of ischemia with no obstructive coronary arteries disease (INOCA) disease. Diagnosis of CMD relies on surrogate physiological indices without objective proof of ischemia. OBJECTIVES: Intracoronary electrocardiogram (icECG) derived hyperemic indices may accurately and objectively detect CMD and reversible ischemia in related territory. METHODS: INOCA patients with proven ischemia by myocardial perfusion scan (MPS) and completely normal coronary arteries underwent simultaneous intracoronary electrophysiological (icECG) and physiological (intracoronary Doppler) assessment in all 3 coronary arteries during rest and under adenosine induced hyperemia. RESULTS: Sixty vessels in 21 patients were included in the final analysis. All patients had at least one vessel with abnormal CFR. 41 vessels had CMD (CFR < 2.5), of which 26 had increased microvascular resistance (structural CMD, HMR > 1.9 mmHg.cm-1.s) and 15 vessels had CMD (CFR < 2.5) with normal microvascular resistance (functional CMD, HMR <= 1.9 mmHg.cm-1.s). Only one-third of the patients (n = 7) had impaired CFR < 2.5 in all 3 epicardial arteries. Absolute ST shift between hyperemia and rest (∆ST) has shown the best diagnostic performance for ischemia (cut-off 0.10 mV, sensitivity: 95%, specificity: 72%, accuracy: 80%, AUC: 0.860) outperforming physiological indices (CFR: 0.623 and HMR: 0.653 DeLong's test P = .0002). CONCLUSIONS: In INOCA patients, CMD involves coronary artery territories heterogeneously. icECG can accurately detect CMD causing perfusion abnormalities in patients with INOCA outperforming physiological CMD markers, by demonstrating actual ischemia instead of predicting the likelihood of inducible ischemia based on violated surrogate thresholds of blunted flow reserve or increased minimum microvascular resistance. CONDENSED ABSTRACT: In 21 INOCA patients with coronary microvascular dysfunction (CMD) and myocardial perfusion scan proved ischemia, hyperemic indices of intracoronary electrocardiogram (icECG) have accurately detected vessel-specific CMD and resulting perfusion abnormalities & ischemia, outperforming invasive hemodynamic indices. Absolute ST shift between hyperemia and rest (∆ST) has shown the best classification performance for ischemia in no Obstructive Coronary Arteries (AUC: 0.860) outperforming Doppler derived CMD indices (CFR: 0.623 and HMR: 0.653 DeLong's test P = .0002).icECG can be used to diagnose CMD causing perfusion defects by demonstrating actual reversible ischemia at vessel-level during the initial CAG session, obviating the need for further costly ischemia tests. CLINICALTRIALS: GOV: NCT05471739.

Coronary microcirculation in nonculprit vessel territory in reperfused acute myocardial infarction.

BACKGROUND: There is an ongoing debate on the extension of reperfusion-related microvascular damage (MVD) throughout the remote noninfarcted myocardial regions in patients with ST-elevation myocardial infarction (STEMI) that undergo primary percutaneous intervention (pPCI). The aim of this study was to elucidate the impact of reperfusion on remote microcirculatory territory by analyzing hemodynamic alterations in the nonculprit-vessel in relation to reperfusion. METHODS: A total of 20 patients with STEMI undergoing pPCI were included. Peri-reperfusion temporal changes in hemodynamic parameters were obtained in angiographically normal nonculprit vessels before and 1-h after reopening of the culprit vessel. Intracoronary pressure and flow velocity data were compared using pairwise analyses (before and 1-h after reperfusion). RESULTS: In the non-culprit vessel, compared to the pre-reperfusion state, mean resting average peak velocity (33.4 ± 9.4 to 25.0 ± 4.9 cm/s, P < 0.001) and mean hyperemic average peak velocity (53.5 ± 14.4 to 42.1 ± 10.66 cm/s, P = 0.001) significantly decreased; whereas baseline (3.2 ± 1.0 to 4.0 ± 1.0 mmHg.cm-1.s, P < 0.001) and hyperemic microvascular resistance (HMR) (1.9 ± 0.6 to 2.4 ± 0.7 mmHg.cm-1.s, P < 0.001) and mean zero flow pressure (Pzf) values (32.5 ± 6.9 to 37.6 ± 8.3 mmHg, P = 0.003) significantly increased 1-h after reperfusion. In particular, the magnitude of changes in HMR and Pzf values following reperfusion were more prominent in patients with larger infarct size and with higher extent of MVD in the culprit vessel territory. CONCLUSION: Reperfusion-related microvascular injury extends to involve remote myocardial territory in relation to the magnitude of the adjacent infarction and infarct-zone MVD. (GUARD Clinical TrialsNCT02732080).

The Interplay between Features of Plaque Vulnerability and Hemodynamic Relevance of Coronary Artery Stenoses.

Fractional flow reserve (FFR) may not be immune from hemodynamic perturbations caused by both vessel and lesion related factors. The aim of this study was to investigate the impact of plaque- and vessel wall-related features of vulnerability on the hemodynamic effect of intermediate coronary stenoses. Methods and Results: In this cross-sectional study, patients referred to catheterization laboratory for clinically indicated coronary angiography were prospectively screened for angiographically intermediate stenosis (50-80%). Seventy lesions from 60 patients were evaluated. Mean angiographic stenosis was 62.1 ± 16.3%. After having performed FFR assessment, intravascular ultrasound (IVUS) was performed over the FFR wire. Virtual histology IVUS was used to identify the plaque components and thin cap fibroatheroma (TCFA). TCFA was significantly more frequent (65 vs. 38%, p = 0.026), and necrotic core volume (26.15 ± 14.22 vs. 16.21 ± 8.93 mm3, p = 0.04) was significantly larger in the positively remodeled than non-remodeled vessels. Remodeling index correlated with necrotic core volume (r = 0.396, p = 0.001) and with FFR (r = -0. 419, p = 0.001). With respect to plaque components, only necrotic core area (r = -0.262, p = 0.038) and necrotic core volume (r = -0.272, p = 0.024) were independently associated with FFR. In the multivariable model, presence of TCFA was independently associated with significantly lower mean FFR value as compared to absence of TCFA (adjusted, 0.71 vs. 0.78, p = 0.034). Conclusion: The current study demonstrated that for a given stenosis geometry, features of plaque vulnerability such as necrotic core volume, TCFA, and positive remodeling may influence the hemodynamic relevance of intermediate coronary stenoses.

[Microvascular obstruction due to thrombosis and fibrin deposition in myocardial infarction]. / Miyokart enfarktüsünde tromboz ve fibrin olusumu ile mikrovasküler tikanmanin gösterilmesi.

OBJECTIVE: It is widely known that myocardial damage is not immediately terminated after the elimination of epicardial occlusion in cases of myocardial infarction. In situ thrombosis during epicardial occlusion might contribute to poor myocardial perfusion after reperfusion of an occluded epicardial artery. In the current study, we sought to determine the effects of ischemia and reperfusion on microvascular thrombotic occlusion. METHODS: Thirty male Wistar rats were included in the study. After the rats had been anesthetized and thoracotomized, the left coronary artery was occluded for 30 minutes in the first group, and it was occluded for 30 minutes and reperfused for an additional 20 minutes in the second group. Ten rats were used as a sham-operated control group. After completion of the study protocol, excised heart preparations were analyzed by immunohistochemistry and electron microscopy. RESULTS: A significant difference was found between the infarction plus reperfusion group and the other 2 groups, with respect to microvascular fibrin and thrombocyte deposition in immunohistochemistry analysis. These results were confirmed by morphological examination with electron microscopy. CONCLUSION: In situ fibrin formation accompanies microvascular obstruction in acute myocardial infarction. Our results indicate that additional therapeutic approaches are needed in order to achieve better tissue perfusion in contemporary treatment of acute myocardial infarction after successful reopening of the infarct-related artery.

A novel method that can be used in both the diagnosis and treatment of peripheral arterial disease in diabetics: vibration-mediated dilation.

OBJECTIVE: The growing incidence of diabetes and the increasing life expectancy of the diabetic population worldwide has increased the number of diabetic vascular complications occurring in cardiology practice. As current treatment and prevention methods are less effective in this patient group, there is a need for new treatment methods in this area. Exercise, which reduces metabolic and vascular problems associated with diabetes, often becomes impossible, especially in advanced-stage patients who need exercise the most. Since exercise and flow-mediated dilation (FMD) are effective by stimulating mechanotransduction mechanisms on the endothelium, it can be expected that the same mechanisms could also be stimulated by direct vibration. METHODS: In order to test this hypothesis, in this study, a group of 20 type 2 diabetes patients (11 males, age 56.80 ± 11.05 years and diagnosed for 15.35 ± 8.61 years) were examined via the application of FMD and vibration-mediated dilation (VMD). We performed vibration for five minutes with 20-Hz frequency and 3-mm vertical amplitude, to the same side forearm, with a 30-minute interval. Using a 10-MHz linear echo probe, brachial artery diameter and flow velocities were recorded for 10 minutes before and at two-minute intervals after the FMD and VMD applications. Then brachial artery flow and resistance were calculated at each stage. RESULTS: In the first minute after FMD and VMD applications, brachial artery diameter and flow velocities increased significantly, and vascular resistance decreased significantly. None of the corresponding FMD or VMD parameters in the first minute was different. The artery diameters in the first minute after FMD and VMD were increased by 6.04 ± 5.29 and 5.49 ± 5.21%, respectively. At the tenth minute, these values decreased to 1.73 ± 3.21 and 2.05 ± 3.31%. In the FMD series, all parameters except brachial artery diameter returned to their baseline values after the fourth minute. After VMD, all parameters also decreased after the first minute, but the recovery was much slower. At each stage after the first minute, the VMD averages were higher than the baseline value and their corresponding FMD values. CONCLUSION: The results of this study indicated that vibration may be a powerful, long-lasting and feasible treatment option in patients with peripheral perfusion failure, developed due to diabetic macro- and microvascular complications.

Primary versus iatrogenic (post-PCI) coronary microvascular dysfunction: a wire-based multimodal comparison.

BACKGROUND: Although there are studies examining each one separately, there are no data in the literature comparing the magnitudes of the iatrogenic, percutaneous coronary intervention (PCI)-induced, microvascular dysfunction (Type-4 CMD) and coronary microvascular dysfunction (CMD) in the setting of ischaemia in non-obstructed coronary arteries (INOCA) (Type-1 CMD). OBJECTIVES: We aimed to compare the characteristics of Type-1 and Type-4 CMD subtypes using coronary haemodynamic (resistance and flow-related parameters), thermodynamic (wave energy-related parameters) and hyperemic ECG changes. METHODS: Coronary flow reserve (CFR) value of <2.5 was defined as CMD in both groups. Wire-based multimodal perfusion markers were comparatively analysed in 35 patients (21 INOCA/CMD and 14 CCS/PCI) enrolled in NCT05471739 study. RESULTS: Both groups had comparably blunted CFR values per definition (2.03±0.22 vs 2.11±0.37; p: 0.518) and similar hyperemic ST shift in intracoronary ECG (0.16±0.09 vs 0.18±0.07 mV; p: 0.537). While the Type-1 CMD was characterised with impaired hyperemic blood flow acceleration (46.52+12.83 vs 68.20+28.63 cm/s; p: 0.017) and attenuated diastolic microvascular decompression wave magnitudes (p=0.042) with higher hyperemic microvascular resistance (p<0.001), Type-4 CMD had blunted CFR mainly due to higher baseline flow velocity due to post-occlusive reactive hyperemia (33.6±13.7 vs 22.24±5.3 cm/s; p=0.003). CONCLUSIONS: The perturbations in the microvascular milieu seen in CMD in INOCA setting (Type-1 CMD) seem to be more prominent than that of seen following elective PCI (Type-4 CMD), although resulting reversible ischaemia is equally severe in the downstream myocardium.

Successful stenting of a left main coronary artery occlusion as a complication of RF ablation for Wolff-Parkinson-White syndrome.

Wolff-Parkinson-White (WPW) syndrome is a disorder characterized by presence of an accessory pathway that predisposes patients to tachyarrhythmias and sudden death. Radiofrequency ablation (RFA) is both effective and safe for patients with symptomatic tachyarrhythmias mediated by accessory atrioventricular pathways. During the procedure, fatal complications may occur but it is considered low in relation to the morbidity associated with the WPW syndrome. Coronary artery occlusion, as a complication of an RF catheter ablation, is quite rare. In this report, we present a 56-year-old male patient with a left main coronary artery (LMCA) occlusion during the ablation of left anterolateral wall accessory pathway. It should be kept in mind if the patient complains of new onset of severe chest pain, an immediate angiography should be performed.

Gradual Versus Abrupt Reperfusion During Primary Percutaneous Coronary Interventions in ST-Segment-Elevation Myocardial Infarction (GUARD).

Background Intramyocardial edema and hemorrhage are key pathological mechanisms in the development of reperfusion-related microvascular damage in ST-segment-elevation myocardial infarction. These processes may be facilitated by abrupt restoration of intracoronary pressure and flow triggered by primary percutaneous coronary intervention. We investigated whether pressure-controlled reperfusion via gradual reopening of the infarct-related artery may limit microvascular injury in patients undergoing primary percutaneous coronary intervention. Methods and Results A total of 83 patients with ST-segment-elevation myocardial infarction were assessed for eligibility and 53 who did not meet inclusion criteria were excluded. The remaining 30 patients with totally occluded infarct-related artery were randomized to the pressure-controlled reperfusion with delayed stenting (PCRDS) group (n=15) or standard primary percutaneous coronary intervention with immediate stenting (IS) group (n=15) (intention-to-treat population). Data from 5 patients in each arm were unsuitable to be included in the final analysis. Finally, 20 patients undergoing primary percutaneous coronary intervention who were randomly assigned to either IS (n=10) or PCRDS (n=10) were included. In the PCRDS arm, a 1.5-mm balloon was used to achieve initial reperfusion with thrombolysis in myocardial infarction grade 3 flow and, subsequently, to control distal intracoronary pressure over a 30-minute monitoring period (MP) until stenting was performed. In both study groups, continuous assessment of coronary hemodynamics with intracoronary pressure and Doppler flow velocity was performed, with a final measurement of zero flow pressure (primary end point of the study) at the end of a 60-minute MP. There were no complications associated with IS or PCRDS. PCRDS effectively led to lower distal intracoronary pressures than IS over 30 minutes after reperfusion (71.2±9.37 mm Hg versus 90.13±12.09 mm Hg, P=0.001). Significant differences were noted between study arms in the microcirculatory response over MP. Microvascular perfusion progressively deteriorated in the IS group and at the end of MP, and hyperemic microvascular resistance was significantly higher in the IS arm as compared with the PCDRS arm (2.83±0.56 mm Hg.s.cm-1 versus 1.83±0.53 mm Hg.s.cm-1, P=0.001). The primary end point (zero flow pressure) was significantly lower in the PCRDS group than in the IS group (41.46±17.85 mm Hg versus 76.87±21.34 mm Hg, P=0.001). In the whole study group (n=20), reperfusion pressures measured at predefined stages in the early reperfusion period showed robust associations with zero flow pressure values measured at the end of the 1-hour MP (immediately after reperfusion: r=0.782, P<0.001; at the 10th minute: r=0.796, P<0.001; and at the 20th minute: r=0.702, P=0.001) and peak creatine kinase MB level (immediately after reperfusion: r=0.653, P=0.002; at the 10th minute: r=0.597, P=0.007; and at the 20th minute: r=0.538, P=0.017). Enzymatic myocardial infarction size was lower in the PCRDS group than in the IS group with peak troponin T (5395±2991 ng/mL versus 8874±1927 ng/mL, P=0.006) and creatine kinase MB (163.6±93.4 IU/L versus 542.2±227.4 IU/L, P<0.001). Conclusions In patients with ST-segment-elevation myocardial infarction, pressure-controlled reperfusion of the culprit vessel by means of gradual reopening of the occluded infarct-related artery (PCRDS) led to better-preserved coronary microvascular integrity and smaller myocardial infarction size, without an increase in procedural complications, compared with IS. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02732080.

Intracardiac masses: Single center experience within 12 years: I-MASS Study.

Objective: The aim of this cross-sectional, retrospective, descriptive study was to review and classify cardiac masses systematically and to determine their frequencies. Methods: The medical records of 64,862 consecutive patients were investigated within 12 years. Every patient with a cardiac mass imaged by transthoracic echocardiography (TTE) and confirmed with an advanced imaging modality such as transesophageal echocardiography (TEE), computed tomography (CT) and/or cardiac magnetic resonance imaging (CMR) was included. Acute coronary syndromes triggering thrombus formation, vegetations, intracardiac device and catheter related thrombi were excluded. Results: Data demonstrated 127 (0.195%) intracardiac masses consisting of 33 (0.050%) primary benign, 3 (0.004%) primary malignant, 20 (0.030%) secondary tumors, 3 (0.004%) hydatid cysts and 68 (0.104%) thrombi respectively. The majority of primary cardiac tumors were benign (91.67%), predominantly myxomas (78.79%), and the less malignant (8.33%). Secondary cardiac tumors were common than the primary malignant tumors (20:3), with male dominancy (55%), lymphoma and lung cancers were the most frequent. Intracardiac thrombi was the majority of the cardiac masses, thrombi accompanying malignancies were in the first range (n = 17, 25%), followed by autoimmune diseases (n = 13, 19.12%) and ischemic heart disease with low ejection fraction (n = 12, 17.65%). Conclusions: This retrospective analysis identified 127 patients with cardiac masses. The majority of benign tumors were myxoma, the most common tumors that metastasized to the heart were lymphoma and lung cancers, and the thrombi associated with malignancies and autoimmune diseases were the most frequent.

Intracoronary streptokinase after primary percutaneous coronary intervention.

BACKGROUND: Microvascular perfusion is often impaired after primary percutaneous coronary intervention (PCI). We proposed that in situ thrombosis might contribute to poor myocardial perfusion in this setting. To test this hypothesis, we evaluated the effect of low-dose intracoronary streptokinase administered immediately after primary PCI. METHODS: Forty-one patients undergoing primary PCI were randomly assigned to receive intracoronary streptokinase (250 kU) or no additional therapy. Two days later, cardiac catheterization was repeated, and coronary hemodynamic end points were measured with the use of a guidewire tipped with pressure and temperature sensors. In patients with anterior myocardial infarction, the deceleration time of coronary diastolic flow was measured with transthoracic echocardiography. At 6 months, angiography, echocardiography, and technetium-99m single-photon-emission computed tomography were performed. RESULTS: Two days after PCI, all measures of microvascular function (means +/-SD) were significantly better in the streptokinase group than in the control group, including coronary flow reserve (2.01+/-0.57 vs. 1.39+/-0.31), the index of microvascular resistance (16.29+/-5.06 U vs. 32.49+/-11.04 U), the collateral-flow index (0.08+/-0.05 vs. 0.17+/-0.07), mean coronary wedge pressure (10.81+/-5.46 mm Hg vs. 17.20+/-7.93 mm Hg), systolic coronary wedge pressure (18.24+/-6.07 mm Hg vs. 33.80+/-11.00 mm Hg), and diastolic deceleration time (828+/-258 msec vs. 360+/-292 msec). The administration of intracoronary streptokinase was also associated with a significantly lower corrected Thrombolysis in Myocardial Infarction frame count (the number of cine frames required for dye to travel from the ostium of a coronary artery to a standardized distal coronary landmark) at 2 days. At 6 months, however, there was no evidence of a difference between the two study groups in left ventricular size or function. CONCLUSIONS: In our pilot trial, the administration of low-dose intracoronary streptokinase immediately after primary PCI improved myocardial reperfusion but not long-term left ventricular size or function. These findings require clarification in a larger trial. (ClinicalTrials.gov number, NCT00302419.)

The accuracy of deceleration time of diastolic coronary flow measured by transthoracic echocardiography in predicting long-term left ventricular infarct size and function after reperfused myocardial infarction.

AIMS: Assessment of microvascular function after reperfused acute myocardial infarction (AMI) provides important insights for myocardial reperfusion and facilitates prediction of long-term left ventricular (LV) function and clinical outcome. In this study, we examined microvascular integrity 48 h after successful primary percutaneous coronary intervention (PCI) and compared predictive accuracy of the intracoronary pressure-wire- and transthoracic Doppler echocardiography-based parameters in the estimation of long-term LV infarct size and function. METHODS AND RESULTS: The study group consisted of 30 anterior AMI patients who were treated successfully with primary PCI. Two days after primary PCI, microvascular integrity was evaluated. Coronary flow reserve (CFR), collateral flow index (CFIp), coronary wedge pressure (CWP), and index of microvascular resistance (IMR) were determined using intracoronary pressure wire. Deceleration time of coronary diastolic flow (DDT) was measured using transthoracic echocardiography. At 6 months, coronary angiography, echocardiography, and infarct size measurement were performed. Area under the curve, sensitivity, and specificity of the indices of microvascular perfusion in the prediction of late-term infarct size were as follows: IMR (0.68 ± 0.15, 69%, 60%), CFR (0.67 ± 0.10, 66%, 59%), CWP (0.69 ± 0.12, 70%, 72%), CFIp (0.64 ± 0.10, 65%, 78%), and DDT (0.68 ± 0.16, 69%, 79%). All of the microvascular perfusion indices, which have been used in this study, had comparable sensitivity and specificity in the prediction of long-term ejection fraction. There were no significant differences between areas under the curve of microvascular perfusion indices in the prediction of long-term infarct size and ejection fraction. CONCLUSION: As a non-invasive parameter, DDT was found to be as accurate as the invasive parameters of microvascular function in estimating long-term infarct size and LV function. Thus, simply measuring DDT in the reperfused infarct-related artery might provide useful and reliable estimate for early risk stratification.

Reducing Aortic Barotrauma and Vascular Extracellular Matrix Degradation by Pacemaker-Mediated QRS Widening.

Background The extent of pressure-related damage might be related to acceleration rate of the applied pressure (peak dP/dt) in the vascular system. In this study, we sought to determine whether dP/dt applied to the aortic wall (aortic dP/dt) and in turn vascular extracellular matrix degradation can be mitigated via modulation of left ventricular (LV) contractility (LV dP/dt) by pacemaker-mediated desynchronization. Methods and Results First, in 34 patients, changes in aortic dP/dt values in 3 aortic segments in response to pacemaker-mediated stepwise QRS widening leading to gradual desynchronization of the LV contraction by means of steadily changed atrioventricular delay (AVD) with temporary dual-chamber pacing was examined before and after beta-blocker (15 mg IV metoprolol) administration. Second, serum matrix metalloproteinase-9 levels were measured in the 20 patients with permanent pacemaker while they were on sinus rhythm with normal QRS width and 3 weeks after wide QRS rhythm ensured by dual pacing, dual sensing, and dual response to sensing with short AVD. LV dP/dt substantially correlated with dP/dt measured in ascending (r=0.83), descending (r=0.89), and abdominal aorta (r=0.96). QRS width strongly correlated with dP/dt measured in ascending (r=-0.95), descending (r=-0.92), and abdominal (r=-0.96) aortic segments as well. In patients with permanent pacemaker, wide QRS rhythm led to a significant reduction in serum matrix metalloproteinase-9 levels (from 142.5±32.9 pg/mL to 87.5±32.4 pg/mL [P<0.001]) at the end of 3 weeks follow-up. Conclusions QRS prolongation by short AVD dual pacing, dual sensing, and dual response to sensing results in concomitant decreases in peak dP/dt values in the LV and in all aortic segments with or without background beta-blocker administration, which in turn led to a significant reduction in circulating matrix metalloproteinase-9 levels. Registration URL: https://www.clini​caltr​ials.gov; Unique identifier: NCT03665558.

Early detection of right ventricular systolic dysfunction by using myocardial acceleration during isovolumic contraction in patients with mitral stenosis.

AIM: The aim of the study was to determine if the tissue Doppler imaging (TDI)-derived myocardial acceleration during isovolumic contraction (IVA) of tricuspid lateral annulus could be used in early detection of RV systolic dysfunction in patients with mitral stenosis (MS), before the clinical signs of systemic venous congestion occur. METHODS: One hundred and twelve patients with rheumatic MS without relevant regurgitation and 60 control subjects were enrolled in the study. Conventional echocardiographic parameters (mitral valve area, transmitral diastolic gradients, pulmonary artery pressure, RV fractional shortening, pulmonary flow acceleration time, tricuspid annular plane systolic excursion) and TDI-derived systolic velocities of tricuspid annulus (isovolumic myocardial acceleration: IVA, peak myocardial velocity during isovolumic contraction: IVV, peak systolic velocity during ejection period: Sa and RV Tei index) were recorded from all patients. RESULTS: TDI-derived IVA, IVV, Sa and Tei index were found to be significantly decreased in patients with MS. IVA was the only parameter which had a significant negative correlation with the traditional echocardiographic parameters and RV Tei index in patients with MS. Additionally, in subgroup analyses, IVA was significantly lower in patients with severe degree of MS. CONCLUSION: TDI-derived right ventricular IVA may be used as an adjunctive, reliable, noninvasive parameter for the early detection of right ventricular systolic dysfunction in patients with MS but without signs of systemic venous congestion.

Hyperaemic microvascular resistance predicts clinical outcome and microvascular injury after myocardial infarction.

OBJECTIVES: Early detection of microvascular dysfunction after acute myocardial infarction (AMI) could identify patients at high risk of adverse clinical outcome, who may benefit from adjunctive treatment. Our objective was to compare invasively measured coronary flow reserve (CFR) and hyperaemic microvascular resistance (HMR) for their predictive power of long-term clinical outcome and cardiac magnetic resonance (CMR)-defined microvascular injury (MVI). METHODS: Simultaneous intracoronary Doppler flow velocity and pressure measurements acquired immediately after revascularisation for AMI from five centres were pooled. Clinical follow-up was completed for 176 patients (mean age 60±10 years; 140(80%) male; ST-elevation myocardial infarction (STEMI) 130(74%) and non-ST-segment elevation myocardial infarction 46(26%)) with median follow-up time of 3.2 years. In 110 patients with STEMI, additional CMR was performed. RESULTS: The composite end point of death and hospitalisation for heart failure occurred in 17 patients (10%). Optimal cut-off values to predict the composite end point were 1.5 for CFR and 3.0 mm Hg cm-1•s for HMR. CFR <1.5 was predictive for the composite end point (HR 3.5;95% CI 1.1 to 10.8), but not for its individual components. HMR ≥3.0 mm Hg cm-1 s was predictive for the composite end point (HR 7.0;95% CI 1.5 to 33.7) as well as both individual components. HMR had significantly greater area under the receiver operating characteristic curve for MVI than CFR. HMR remained an independent predictor of adverse clinical outcome and MVI, whereas CFR did not. CONCLUSIONS: HMR measured immediately following percutaneous coronary intervention for AMI with a cut-off value of 3.0 mm Hg cm-1 s, identifies patients with MVI who are at high risk of adverse clinical outcome. For this purpose, HMR is superior to CFR.

Acute anterior myocardial infarction after chemotherapy for testicular seminoma in a young patient.

Testicular cancer is the most common solid tumor among young men aged 15 to 35 years. Combination chemotherapy with cisplatin, etoposide, and bleomycin remains the mainstay of treatment. We present a 27-year-old man who presented with an acute anterior myocardial infarction during the second course of chemotherapy for seminoma. Because the patient had no significant risk factors for coronary heart disease, the infarction was likely caused by the chemotherapy regimen.

Coronary microvascular dysfunction equivalent to left main coronary artery disease.

Coronary microvascular dysfunction, also known as cardiac syndrome X, is a clinical syndrome presenting with typical angina and evidence of myocardial ischemia in the absence of flow-limiting stenosis on coronary angiography. Of patients undergoing coronary angiography due to suspected myocardial ischemia, 50% are found to have normal or near-normal coronary arteries. Described in this case report is a patient who developed hypotension and ST segment depressions during treadmill exercise test. Left main coronary artery or multivessel disease was suspected. Coronary angiography was normal, but coronary flow reserve measurement revealed severe microvascular dysfunction.

Influence of coronary calcification patterns on hemodynamic outcome of coronary stenoses and remodeling.

OBJECTIVE: The histological characteristics of plaque may affect the hemodynamic outcome of a given coronary stenosis. In particular, the potential effect of volumetric calcium content and the topographical distribution in the lesion segment on physiological outcome has not yet been investigated. The aim of this study was to identify any potential correlation between patterns of calcification and the fractional flow reserve (FFR) and the coronary remodeling index (RMI). METHODS: A total of 26 stable angina pectoris and 34 acute coronary syndrome patients without persistent ST-segment elevation constituted the study population. FFR was used to assess 70 intermediate coronary stenosis lesions. After obtaining hemodynamic measurements, quantitative grayscale and virtual histology-intravascular ultrasound analyses were performed. The depth, length, and circumferential distribution of calcification of the lesions were also recorded. RESULTS: Within the analyzed segment (area of interest, lesion segment), FFR was correlated with maximal thickness of deep calcification (r=-0.285; p=0.021) and calcification angle (r=-0.396; p=0.001). In lesions with a calcification angle >180°, the mean FFR value was significantly lower compared with those <180° (0.64±0.17 vs. 0.78±0.08; p=0.024). RMI was correlated with maximal angle of superficial (r=-0.437; p<0.001) and deep (r=0.425; p<0.001) calcification. RMI was correlated with maximal thickness of superficial (r=-0.357; p=0.003) and deep (r=0.417; p<0.001) calcification. RMI was also correlated with FFR (r=-0.477; p<0.001). CONCLUSION: This study demonstrated that the geometry, location, and amount of calcification of a plaque could affect hemodynamic and anatomical outcome measures in functionally significant stenoses by affecting vessel wall compliance.

Pressure-derived collateral flow index: a strong predictor of late left ventricular remodeling after thrombolysis for acute myocardial infarction.

OBJECTIVE: Despite proved efficacy of pressure-derived collateral flow index in determining microvascular dysfunction in patients with acute myocardial infarction, its role in prediction of left ventricular remodeling at long term has yet to be demonstrated. In this study, we investigated the relationship between quantitatively assessed microvascular dysfunction by using intracoronary pressure wire and late left ventricular remodeling. PATIENTS AND METHODS: The study population consisted of 28 patients with first acute myocardial infarction. They were treated with fibrinolytic therapy. The inclusion criteria were thrombolysis in myocardial infarction grade II-III flow in infarct-related artery and all destined for stent implantation. Cardiac catheterization and stent implantation were performed in mean of 3.3 days after acute myocardial infarction. During the stent implantation procedure, the pressure-derived collateral flow index was measured by using intracoronary pressure wire. Control angiograms were performed at 6+/-2 months. Echocardiographic left ventricular volume indexes were measured at discharge, at 6 months and at 1 year. Changes in left ventricular volumes from baseline to 1 year were followed. RESULTS: Left ventricular end-diastolic volume index at 1 year correlated significantly with the pressure-derived collateral flow index (r=0.69, P<0.01). A significant correlation was also observed between the change in left ventricular end-diastolic volume index from baseline to 1 year and the pressure-derived collateral flow index (r=0.65, P<0.01). The most important predictor of 1-year left ventricular remodeling was the pressure-derived collateral flow index (P<0.0001), and collateral circulation (P=0.03). CONCLUSION: The pressure-derived collateral flow index is a powerful independent predictor of 1-year left ventricular dilatation. Given its simplicity of measurement, and correlation with microvascular obstruction and left ventricular outcome at long term, the pressure-derived collateral flow index may provide useful and valuable estimates of clinical outcomes after acute myocardial infarction.