Cardiomyopathic syndrome due to coronary artery disease. I: Relation to angiographic extent of coronary disease and to remote myocardial infarction

Myocardial mass affects diagnostic performance of non-hyperemic pressure-derived indexes in the assessment of coronary stenosis

Background Several non-hyperemic pressure-derived Indexes (NHPI) have been introduced for the assessment of coronary stenosis, showing a good correlation with fractional flow reserve (FFR). Notably, either the assessment of NHPI during adenosine administration (NHPI_ADO) or the Hybrid Approach (NHPI_HA), combining NHPI with FFR, have been showed to increase the accuracy of such indexes. It remains unclear whether diagnostic performance might be affected by the extent of the subtended myocardial mass.

METHODS

We enrolled consecutive patients with an intermediate coronary stenosis assessed with NHPI and FFR. NHPI were also measured during adenosine (ADO) administration (NHPI_ADO). The amount of jeopardized myocardium was assessed using the Duke Jeopardy Score (DJS). With FFR as reference, we assessed the accuracy of NHPI, NHPI_ADO and NHPI_HA according to the extent of the subtended myocardium.

RESULTS

One-hundred-seventy stenoses from 151 patients were grouped according to the DJS as follows: A) Small Extent (SE, n = 82); B) Moderate Extent (ME, n = 53); C) Large Extent (LE, n = 35). As compared with FFR, NHPI showed a significantly different accuracy, as assessed by the Youden's index, according to the extent of the jeopardized myocardium (SE: 0.39 ± 0.05, ME: 0.68 ± 0.06, LE: 0.28 ± 0.06, p < 0.001). Conversely, both the NHPI_ADO (SE: 0.76 ± 0.02, ME: 0.88 ± 0.02, LE: 0.82 ± 0.02, p = 0.72) and NHPI_HA (SE: 0.82 ± 0.07, ME: 0.84 ± 0.02, LE: 0.88 ± 0.02, p = 0.70) allowed for a better diagnostic accuracy regardless of the amount of myocardium subtended.

CONCLUSIONS

Diagnostic performance of NHPI might be affected by the extent of myocardial territory subtended by the coronary stenosis. A hybrid approach might be useful to overcome this limitation.

Hybrid Imaging to Assess the Impact of Vulnerable Plaque on Post Myocardial Infarction Myocardial Scar

Background: Multimodality imaging improves the accuracy of cardiac assessment in patients with prior myocardial infarction. The aim of this study was to investigate the association between coronary plaque vulnerability (PV) and myocardial viability in the territory irrigated by the infarct-related artery (IRA). Secondary objectives include evaluation of the systemic inflammation but also different cardiac risk scores (SYNTAX score, Duke jeopardy score, or calcium score) using hybrid imaging models of coronary computed tomography angiography (CCTA) and cardiac magnetic resonance (CMR) in patients who have suffered a previous myocardial infarction (MI). Material and methods: The study included 45 subjects with documented MI in the 30 days prior to study enrolment, who underwent CCTA and CMR examinations. Computational postprocessing of CCTA and CMR images was used to generate fused imaging models. Based on the vulnerability degree of the associated non-culprit lesion located proximally in the IRA, the study population was divided into 3 groups: Group 1 – subjects with no sign of vulnerability (n = 7); Group 2 – subjects with 1 or 2 CT vulnerability features (n = 28); and Group 3 – subjects with >2 features of vulnerability (n = 12). Results: CCTA features indicative for the severity of coronary artery disease were not different between groups in terms of calcium scoring (460 ± 501 vs. 579 ± 430 vs. 432 ± 494, p = 0.7) or SYNTAX score (25 ± 9.2 vs. 24.9 ± 8.3 vs. 20.2 ± 11.9, p = 0.4). However, after 1 month, infarct size and the Duke jeopardy score were associated with increased PV (infarct size 8.77 ± 3.4 g in Group 1, compared to 20.87 ± 8.3 g in Group 2 and 27.99 ± 11.8 g in Group 3 (p = 0.007), while the Duke jeopardy score was 4.4 ± 1.6 in Group 1, vs. 7.07 ± 2.1 in Group 2 vs. 7.5 ± 1.73 in Group 3 (p = 0.01). Inflammatory biomarkers were directly associated with coronary plaque vulnerability (p = 0.007 for hs-CRP and p = 0.038 for MMP-9). Conclusion: In patients with prior myocardial infarction, the size of myocardial scar was directly correlated with the vulnerability degree of coronary plaques and with systemic inflammation quantified during the acute phase of the coronary event. Hybrid imaging may help to identify the hemodynamically significant plaques with superior accuracy.

ADDED Index or percentage diameter of residual coronary stenosis to risk-stratify patients presenting with STEMI

BACKGROUND

We compared the prognostic value of the ADDED Index with visually estimated diameter (DS) of residual coronary stenosis (RS) in STEMI patients after successful PCI of the culprit lesion. Even though associated with a positive outcome, the functional assessment of non-culprit stenosis remains largely underused, especially in STEMI patients. The Angiography-DeriveD hEmoDynamic index (ADDED index) showed high accuracy to predict FFR and it might be used to better guide the diagnostic and therapeutic work-up of such patients.

METHODS

We retrospectively included 596 patients grouped on the basis of either the ADDED Index (ADDED Negative (<2.23, n = 153) vs ADDED Positive (≥2.23, n = 129)) or the DS of the RS (RS Negative (<50%, n = 177) vs RS Positive (≥50%, n = 105)). Patients without any RS served as control (n = 314). Primary endpoints were: 1) major adverse cardiac events (MACE), composite of all-cause death, myocardial infarction (MI), clinically driven revascularizations (CDR); 2) non-culprit vessel oriented clinical events (VOCE), composite of all-cause death, non-culprit vessel related MI and CDR.

RESULTS

At 24 months the rate of both MACE and VOCE was significantly higher in both the ADDED Positive and RS Positive groups. However, differently from patients in whom complete revascularization was deferred on the basis of the angiography (RS Negative), no additional risk was found for patients in the ADDED Negative group.

CONCLUSIONS

In STEMI patients with MVD deferring treatment of RS on the basis of the ADDED index, rather than the visually estimated DS, is associated with a favorable clinical outcome.

Interaction between a haptoglobin genetic variant and coronary artery disease (CAD) risk factors on CAD severity in Singaporean Chinese population

BACKGROUND

Haptoglobin (Hp) is a plasma protein with strong anti-inflammation and antioxidant activities. Its plasma level is known to be inversely associated with many inflammatory diseases, including cardiovascular diseases. However, the association of HP genetic variants with coronary artery disease (CAD) severity/mortality, and how they interact with common CAD risk factors are largely unknown.

METHODS

We conducted the analysis in a Singaporean Chinese CAD population with Gensini severity scores (N = 582) and subsequently evaluated the significant findings in an independent cohort with cardiovascular mortality (excluding stroke) as outcome (917 cases and 19,093 controls). CAD risk factors were ascertained from questionnaires, and stenosis information from medical records. Mortality was identified through linkage with the nationwide registry of births and deaths in Singapore. Linear regression analysis between HP genetic variant (rs217181) and disease outcome were performed. Interaction analyses were performed by introducing an interaction term in the same regression models.

RESULTS

Although rs217181 was not significantly associated with CAD severity and cardiovascular mortality (excluding stroke) in all subjects, when stratified by hypertension status, hypertensive individuals with the minor T allele have more severe CAD (β = 0.073, SE = 0.030, p = 0.015) and non-hypertensive individuals with the T allele have lower risk for mortality (odds ratio = 0.771 (0.607-0.980), p = 0.033).

CONCLUSION

HP genetic variant is not associated with CAD severity and mortality in the general population. However, hypertensive individuals with the rs217181 T allele associated with higher Hp levels had more severe CAD while non-hypertensive individuals with the same allele had lower risk for mortality in the Chinese population.

Strategy for Disease Diagnosis, Progression Prediction, Risk Group Stratification and Treatment-Case of COVID-19

A novel strategy is presented for reliable diagnosis and progression prediction of diseases with special attention to COVID-19 pandemic. A plan is presented for how the model can be implemented worldwide in healthcare and how novel treatments and targets can be detected. The idea is based on poikilosis, pervasive heterogeneity, and variation at all levels, systems, and mechanisms. Poikilosis in diseases can be taken into account in pathogenicity model, which is based on distribution of three independent condition measures-extent, modulation, and severity. Pathogenicity model is a population or cohort-based description of disease components. Evidence-based thresholds can be applied to the pathogenicity model and used for diagnosis as well as for early detection of patients in risk of developing the most severe forms of the disease. Analysis of patients with differential course of disease can help in detecting biomarkers of diagnostic and prognostic significance. A practical and feasible plan is presented how the concepts can be implemented in practice. Collaboration of many actors, including the World Health Organization and national health authorities, will be essential for success.

Does an occluded RCA affect prognosis in patients undergoing PCI or CABG for left main coronary artery disease? Analysis from the EXCEL trial

AIMS

The impact of an occluded right coronary artery (RCA) in patients with left main coronary artery disease (LMCAD) undergoing revascularisation is unknown. We compared outcomes for patients with LMCAD randomised to percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) according to the presence of an occluded RCA in the EXCEL trial.

METHODS AND RESULTS

The EXCEL trial randomised 1,905 patients with LMCAD and SYNTAX scores ≤32 to PCI with everolimus-eluting stents versus CABG. Patients were categorised according to whether they had an occluded RCA at baseline, and their outcomes were examined using multivariable Cox proportional hazards regression. The primary endpoint was a composite of death, stroke, or myocardial infarction at three years. Among 1,753 patients with a dominant RCA by core laboratory analysis, the RCA was occluded in 130 (7.4%) at baseline. PCI was attempted in 34 of 65 patients with an occluded RCA (52.3%) and was successful in 27 (79.4% of those attempted; 41.5% of all RCAs recanalised). The RCA was bypassed in 42 of 65 patients with an occluded RCA (64.6%; p=0.0008 versus PCI). The three-year absolute and relative rates of the primary endpoint were similar between PCI and CABG, in patients with or without an occluded RCA (pinteraction=0.92).

CONCLUSIONS

In the EXCEL trial, the presence of an occluded RCA at baseline did not confer a worse three-year prognosis in patients undergoing revascularisation for LMCAD and did not affect the relative outcomes of PCI versus CABG in this high-risk patient cohort.

Prognostically Significant Myocardial Injury in Patients Undergoing Transcatheter Aortic Valve Replacement

Background

Troponin elevation occurs commonly in the setting of transcatheter aortic valve replacement (TAVR). There is a lack of information on the extent of troponin elevation post TAVR that is prognostically significant. We assessed the optimal cutoff for post‐TAVR troponin T elevation that correlates with long‐term mortality. We also examined the relationship between coronary artery disease (CAD) and prognostically significant myocardial injury in TAVR.

Methods and Results

This is a retrospective, observational single‐center study involving patients who underwent TAVR at Cleveland Clinic between 2010 and 2015. Five hundred ten patients were included (mean follow‐up of 2.6±1.3 years). Receiver operating characteristic analysis showed that troponin T elevation ≥3× upper limit of normal was the best predictor of long‐term mortality post TAVR with area under the curve of 0.57, with transapical TAVR patients excluded. Multivariate analyses confirmed that troponin T elevation ≥3× upper limit of normal was significantly associated with increased long‐term mortality post TAVR (hazard ratio 1.57, CI 1.04–2.38, P=0.03). The most common causes for the presence of unrevascularized CAD included the presence of chronic total occlusion in the native/graft vessels (49.7%) and diffuse/complex CAD unsuitable for PCI (24.6%). The presence of unrevascularized CAD and significant left main disease correlated with increased mortality, but not with the presence of prognostically significant myocardial injury.

Conclusions

Troponin T elevation of ≥3× upper limit of normal is associated with increased long‐term mortality after TAVR, except for the transapical approach. This prognostically significant myocardial injury does not appear to be secondary to severe CAD/unrevascularized CAD or left main disease, but rather is associated with other factors such as post‐TAVR complications.

Influence of the amount of myocardium subtended to a coronary stenosis on the index of microcirculatory resistance. Implications for the invasive assessment of microcirculatory function in ischaemic heart disease

AIMS

The index of microcirculatory resistance (IMR) is increasingly used to quantify microcirculatory function. However, in normal coronary arteries, resistance increases with the branching structure of the coronary tree, which suggests that IMR could be influenced by the amount of downstream myocardial mass (MM). We aimed to evaluate the influence of the amount of MM subtended to an intermediate stenosis on the IMR.

METHODS AND RESULTS

IMR, fractional flow reserve and coronary flow reserve (CFR) were measured in 123 coronary arteries (102 patients) with intermediate stenosis. Jeopardised MM was estimated with the Myocardial Jeopardy Index (MJI). MM was inversely associated with IMR (R.

Relationship of the Duke jeopardy score combined with minimal lumen diameter as assessed by computed tomography angiography to the hemodynamic relevance of coronary artery stenosis

OBJECTIVES

To study the diagnostic performance of the ratio between the Duke jeopardy score (DJS) and the minimal lumen diameter (MLD) (DJS/MLD_CT ratio) as assessed by coronary computed tomographic angiography (CTA) for differentiating functionally significant from non-significant coronary artery stenoses, with reference to invasive fractional flow reserve (FFR).

METHODS

Patients who underwent both coronary CTA and FFR measurement during invasive coronary angiography (ICA) within 2 weeks were retrospectively included in the study. Invasive FFR measurement was performed in patients with intermediate to severe coronary stenoseis. DJS/MLD_CT ratio and anatomical parameters were recorded. Lesions with FFR ≤0.80 were considered to be functionally significant.

RESULTS

One hundred and sixty-one patients with 175 lesions were included into the analysis. Diameter stenosis in CT, area stenosis, plaque burden, lesion length (LL), ICA-based stenosis degree, DJS, LL/MLD⁴ ratio, DJS/MLA ratio as well as DJS/MLD ratio were all significantly different between hemodynamically significant and non-significant lesions (p<0.05 for all). ROC curve analysis determined the optimal cut-off value for DJS/MLD_CT ratio to be 1.96 (area under curve = 0.863, 95 % confidence interval = 0.803-0.910), yielding a high diagnostic accuracy (86.9%, 152/175).

CONCLUSIONS

In coronary artery stenoses detected by coronary CTA, the DJS/MLD ratio is able to predict hemodynamic relevance.

The Relationship between Body Mass Index and the Severity of Coronary Artery Disease in Patients Referred for Coronary Angiography

Background and Aim. Obesity is associated with an increased risk of cardiovascular disease and may be associated with more severe coronary artery disease (CAD); however, the relationship between body mass index [BMI (kg/m²)] and CAD severity is uncertain and debatable. The aim of this study was to examine the relationship between BMI and angiographic severity of CAD. Methods. Duke Jeopardy Score (DJS), a prognostic tool predictive of 1-year mortality in CAD, was assigned to angiographic data of patients ≥18 years of age (N = 8,079). Patients were grouped into 3 BMI categories: normal (18.5–24.9 kg/m²), overweight (25.0–29.9 kg/m²), and obese (≥30 kg/m²); and multivariable adjusted hazard ratios for 1-year all-cause and cardiac-specific mortality were calculated. Results. Cardiac risk factor prevalence (e.g., diabetes, hypertension, and hyperlipidemia) significantly increased with increasing BMI. Unadjusted all-cause and cardiac-specific 1-year mortality tended to rise with incremental increases in DJS, with the exception of DJS 6 (p < 0.001). After adjusting for potential confounders, no significant association of BMI and all-cause (HR 0.70, 95% CI .48–1.02) or cardiac-specific (HR 1.11, 95% CI .64–1.92) mortality was found. Conclusions. This study failed to detect an association of BMI with 1-year all-cause or cardiac-specific mortality after adjustment for potential confounding variables.

Integration of non-invasive functional assessments with anatomical risk stratification in complex coronary artery disease: the non-invasive functional SYNTAX score

Since the early days of coronary angiography, the extension and severity of coronary artery disease (CAD) have been used for risk stratification. The SYNTAX score objectively characterizes CAD in patients with multivessel disease. Furthermore, recalculating the SYNTAX score by the incorporation of the functional component coronary stenosis (i.e., FFR) increases the discrimination for the risk of adverse events. The calculation of the SYNTAX score derived from non-invasive modalities such as coronary computed tomography angiography (CTA) has emerged as a mean to obtain the SYNTAX score before invasive cardiac catheterization. Likewise, the computation of the non-invasive fractional flow reserve CT (FFR_CT) allows for the calculation of the non-invasive functional SYNTAX score. Ultimately, the combination of anatomical and functional evaluations with clinical factors further refines the identification of patients at risk and provides a recommendation for the Heart Team regarding the treatment strategy (i.e., PCI or CABG) based on the predicted 4-year mortality. The purpose of this review is to describe the integration of a novel non-invasive functional coronary assessment with the angiographic risk score in patients with multivessel CAD.

How to Define Pathogenicity, Health, and Disease?

Scientific and clinical communities produce ever increasing amounts of data and details about health and disease. Our ability to understand and utilize this information is limited because of imprecise language and lack of well-defined concepts. This problem involves also the principal concepts of health, disease, and pathogenicity. Here, a systematic model is presented for pathogenicity, as well as for health and disease. It has three components: extent, modulation, and severity, which jointly define the continuum of pathogenicity. The model is population based, and once implemented, it can be used for numerous purposes such as diagnosis, patient stratification, prognosis, finding phenotype-genotype correlations, or explaining adverse drug reactions. The new model has several benefits including health economy by allowing evidence-based personalized/precision medicine.

Factors Associated With Errors in Visual Estimation of the Functional Significance of Coronary Lesions

INTRODUCTION AND 

OBJECTIVES

Visual angiographic assessment continues to be used when decisions are made on whether to revascularize ambiguous coronary lesions. Multiple factors, other than the degree of stenosis, have been associated with the functional significance of a coronary lesion. The aim of this study was to investigate the ability of interventionists to visually predict the functional significance of a coronary lesion and the clinical and angiographic characteristics associated with errors in prediction.

METHODS

We conducted a concordance study of the functional significance of coronary lesions predicted by experienced interventionists and fractional flow reserve values measured by intracoronary pressure wire in 665 intermediate lesions (40%-70% diameter stenosis) in 587 patients. We determined which factors were independently associated with errors in prediction.

RESULTS

There was disagreement between the predicted fractional flow reserve value of ≤ 0.80 and the observed value in 30.1% of the lesions (overestimation: 11.3%; underestimation, 18.8%). Stent location in an artery other than the anterior descending artery or in a bifurcation was associated with overestimation. Male sex, severe calcification, and a greater myocardial territory distal to the lesion were significantly associated with the functional significance of the underestimated lesion.

CONCLUSIONS

Even when taking into account angiographic and clinical characteristics, there is a high rate of disagreement between visual estimation and direct measurement of intermediate coronary stenosis in relation to its functional significance. Specific angiographic and clinical characteristics are associated with an increased tendency to overestimate or underestimate the significance of lesions.

The Same Angiographic Factors Predict Venous and Arterial Graft Patency: A Retrospective Study

To evaluate the value of angiographic factors in predicting failure of both venous and arterial coronary artery bypass graft. We retrieved from our angiographic database 148 patients who underwent venous and/or arterial CABG and for whom a control coronary angiography at more than 1 month after surgery was available. Pre-CABG and follow-up angiographies were analyzed in order to evaluate diameter stenosis (DS,%), stenosis length (mm), Bogaty score (extent index), Sullivan score, and Gensini score for the extent of coronary artery disease, and Jeopardy Duke score for the extent of myocardial area supplied by an artery. Thirty-nine patients (26%) experienced graft failure at follow-up (mean follow-up 11.3 ± 4.6 months). Patients with venous graft failure [26 (20%)] had significantly smaller DS (P = 0.013), shorter stenosis length (P = 0.01), and lower extent index (P = 0.015), Sullivan score (P = 0.013), Gensini score (P = 0.04) as compared with those without venous graft failure. Patients with arterial graft failure [13 (11%)] had significantly lower DS (P = 0.008), shorter stenosis length (P = 0.001), and lower extent index (P = 0.03) and Sullivan score (P = 0.023) as compared with those without arterial graft failure. Venous and arterial graft failure are associated with less severe stenosis and less extensive atherosclerosis of the grafted vessel.

Developments in surgical revascularization to achieve improved morbidity and mortality

Coronary artery bypass graft surgery remains the main treatment modality for multivessel coronary artery disease and has consistently been demonstrated to have significantly lower rates of major adverse cardiac and cerebrovascular events in comparison to percutaneous coronary intervention. In this article we will explore the advances over time and the recent refinements in the techniques of surgical revascularization and how these contribute to the superior outcome profile associated with coronary artery bypass graft surgery. These include the current outcome status of coronary artery bypass grafting; the major landmark trials, registries and meta-analyses comparing coronary artery bypass grafting and percutaneous coronary intervention; the developments in coronary artery disease lesion classification; the techniques for the physiological assessment of coronary artery lesions; bypass grafting using arterial conduits; the role of off-pump coronary artery surgery; the outcomes of reoperative surgery; hybrid techniques for coronary revascularization; minimally invasive coronary artery surgery and finally robotic surgery.

Is the relationship of body mass index to severity of coronary artery disease different from that of waist-to-hip ratio and severity of coronary artery disease? Paradoxical findings

Background

Although for decades there has been controversy regarding the relationship between obesity and coronary artery disease (CAD), it has been assumed that high body mass index (BMI) is a risk factor for CAD. However, the findings of some recent studies were paradoxical.

Objectives

The aim of this study was to find a relationship between high BMI and waist-to-hip ratio (WHR) with severity of CAD.

Methods

This study was a cross-sectional, prospective study where 414 patients with suspected coronary artery disease, in whom coronary angiography was performed, were enrolled. The mean ± SD of their ages was 61.2 ± 27.4 years (range 25–84), and 250 (60.4%) were male. Regarding cardiovascular risk factors, 113 (27.3%) patients had a history of diabetes mellitus (DM), 162 (39.1%) had hypercholesterolaemia, 238 (57.4%) had hypertension, 109 (26.3%) were current smokers and 24 (5.8%) had a family history of CAD. The mean ± SD of the patients’ BMI was 26.04 ± 4.08 kg/m² (range 16–39) and means ± SD of their WHR ranged from 0.951 ± 0.07 to 0.987 ± 0.05. The mean ± SD of the severity of CAD according to the SYNTAX and Duke scores were 17.7 ± 9.6 (range 0–64) and 3.2 ± 1.7 (range 0–12), respectively.

Results

In this study, findings showed a negative correlation between the severity of CAD and BMI, according to both SYNTAX and Duke scores (p ≤ 0.001 and p = 0.001, respectively). However, there was a positive correlation between WHR and severity of CAD, according to the Duke score (p = 0.03).

Conclusion

BMI had a negative correlation with the severity of CAD, but waist-to-hip ratio had a positive correlation with severity of CAD.

Impact of classic and paradoxical low flow on survival after aortic valve replacement for severe aortic stenosis

BACKGROUND

Low flow (LF) can occur with reduced (classic) or preserved (paradoxical) left ventricular ejection fraction (LVEF).

OBJECTIVES

The objective of this study was to compare outcomes of patients with low ejection fraction (LEF), paradoxical low flow (PLF), and normal flow (NF) after aortic valve replacement (AVR).

METHODS

We examined 1,154 patients with severe aortic stenosis (AS) who underwent AVR with or without coronary artery bypass grafting.

RESULTS

Among these patients, 206 (18%) had LEF as defined by LVEF of <50%; 319 (28%) had PLF as defined by LVEF of ≥50% but stroke volume indexed to body surface area (SVi) of ≤35 ml ∙ m(-2); and 629 (54%) had NF, as defined by LVEF of ≥50% and SVi of >35 ml ∙ m(2). Aortic valve area was lower in low flow/LVEF groups (LEF: 0.71 ± 0.20 cm(2) and PLF: 0.65 ± 0.23 cm(2) vs. NF: 0.77 ± 0.18 cm(2); p < 0.001). The 30-day mortality was higher (p < 0.001) in LEF and PLF groups than in the NF group (6.3% and 6.3% vs. 1.8%, respectively). SVi and PLF group were independent predictors of operative mortality (odds ratio [OR]: 1.18, p < 0.05; and OR: 2.97, p = 0.004; respectively). At 5 years after AVR, overall survival was 72 ± 4% in LEF group, 81 ± 2% in PLF group, and 85 ± 2% in NF group (p < 0.0001).

CONCLUSIONS

Patients with LEF or PLF AS have a higher operative risk, but pre-operative risk score accounted only for LEF and lower LVEF. Patients with LEF had the worst survival outcome, whereas patients with PLF and normal flow had similar survival rates after AVR. As a major predictor of perioperative mortality, SVi should be integrated in AS patients' pre-operative evaluation.

Usefulness of the ankle-brachial index to predict high coronary SYNTAX scores, myocardium at risk, and incomplete coronary revascularization

Peripheral artery disease (PAD) is strongly associated with coronary artery disease and poor outcomes after coronary revascularization. The aim of this study was to test the hypothesis that patients with PAD diagnosed by a low ankle-brachial index (ABI; ≤0.90) have more complex coronary artery disease and more myocardium at risk than patients with normal ABIs (1.00 to 1.40) and that subsequent coronary revascularization is less complete. Adults referred for coronary angiography underwent ABI measurement using a standard Doppler ultrasound technique. Blinded reviewers calculated SYNTAX scores and Duke jeopardy scores at baseline and 3 months after angiography. Of 814 patients, 8% had PAD (ABI ≤0.90), 9% had borderline PAD (ABI 0.91 to 0.99), 77% were normal (ABI 1.00 to 1.40), and 7% had vascular calcification artifact (ABI >1.40). Patients with PAD were more likely to have high SYNTAX scores (≥33), with an odds ratio of 4.3 (95% confidence interval 1.2 to 14.9), compared with those with normal ABIs after adjustment for traditional cardiovascular risk factors. Similarly, there was a positive association between baseline high Duke jeopardy score (≥8) and PAD (adjusted odds ratio 3.5, 95% confidence interval 1.7 to 7.1). Postrevascularization high Duke jeopardy scores (≥5) were also positively associated with PAD (adjusted odds ratio 3.0, 95% confidence interval 1.1 to 8.8). In conclusion, PAD is associated with higher SYNTAX scores, more myocardium at risk, and less complete coronary revascularization than in patients with normal ABIs. More complex coronary artery disease and incomplete revascularization may contribute to worse cardiovascular outcomes in patients with PAD.

Correlation Between Ankle Brachial Index and Coronary Artery Disease Severity in Elderly Egyptians

We investigated the association between ankle brachial index (ABI) and coronary heart disease (CHD) severity in elderly Egyptians using different measures. We conducted a case–control study from November 2010 to June 2012 including 200 male and female patients with ischemia ≥60 years who were divided into 100 cases and 100 controls according to ABI and redivided according to age. They underwent coronary angiography followed by ABI measurement using a hand-held Doppler. The CHD severity was estimated using the SYNTAX and Jeopardy scores and number of diseased vessels, which increased significantly in patients with peripheral artery disease ( P < .001) for all. All 3 measures had strong negative correlation with ABI ( P ≤ .001 for Jeopardy, <.001 for SYNTAX scores, and .004 for number of diseased vessels) and were correlated with each other. We concluded that ABI can reflect CHD severity in elderly Egyptians.

Impact of coronary artery disease on left ventricular ejection fraction recovery following transcatheter aortic valve implantation

OBJECTIVES

The objective of the present study was to assess if the presence and severity of CAD is associated with decreased LVEF recovery after TAVI.

BACKGROUND

Coronary artery disease (CAD) and low left ventricular ejection fraction (LVEF) are common findings in patients undergoing transcatheter aortic valve implantation (TAVI). The impact of CAD on LVEF recovery after TAVI has not been specifically evaluated.

METHODS

All patients with LVEF≤50% who underwent TAVI between March 2006 and May 2012 were included in the study. The presence and severity of coronary artery disease was measured using the Duke Myocardial Jeopardy Score (DMJS). A DMJS = 0 corresponds to patients without CAD or complete revascularization and a DMJS > 0 to those with incomplete revascularization. LVEF recovery was assessed by transthoracic echocardiography, measuring the change in LVEF from baseline to 3-months post-TAVI. Myocardial viability was evaluated in a subgroup of patients using cardiac magnetic resonance (CMR) imaging pre-TAVI.

RESULTS

Fifty-six patients were included in the study. Twenty-eight patients (50%) had a DMJS > 0. At 3 months, patients with incomplete revascularization (DMJS > 0) demonstrated less LVEF recovery post-TAVI (2.0 ± 9.2% versus 11.7 ± 8.9% if DMJS = 0; P = 0.001). On multivariate analysis, DMJS and presence of significant delayed-enhancement were found to be independent predictors of LVEF recovery. Patients with incomplete revascularization exhibited a worse prognosis with higher mortality at 30-days (22.2% versus 0% if DMJS = 0; P = 0.010) and 1-year (25.9% versus 3.5% if DMJS = 0; P = 0.019).

CONCLUSIONS

The present study demonstrates an independent association between incomplete revascularization and decreased LVEF recovery in patients with left ventricular dysfunction undergoing TAVI for severe aortic stenosis.

Coronary angiographic scoring systems: an evaluation of their equivalence and validity

BACKGROUND

Multiple scoring systems have been devised to quantify angiographic coronary artery disease (CAD) burden, but it is unclear how these scores relate to each other and which scores are most accurate. The aim of this study was to compare coronary angiographic scoring systems (1) with each other and (2) with intravascular ultrasound (IVUS)-derived plaque burden in a population undergoing angiographic evaluation for CAD.

METHODS

Coronary angiographic data from 3600 patients were scored using 10 commonly used angiographic scoring systems and interscore correlations were calculated. In a subset of 50 patients, plaque burden and plaque area in the left anterior descending coronary artery were quantified using IVUS and correlated with angiographic scores.

RESULTS

All angiographic scores correlated with each other (range for Spearman coefficient [ρ] 0.79-0.98, P < .0001); the 2 most widely used scores, Gensini and CASS-70, had a ρ = 0.90 (P < .0001). All scores correlated significantly with average plaque burden and plaque area by IVUS (range ρ 0.56-0.78, P < .0001 and 0.43-0.62, P < .01, respectively). The CASS-50 score had the strongest correlation (ρ 0.78 and 0.62, P < .0001) and the Duke Jeopardy score the weakest correlation (ρ 0.56 and 0.43, P < .01) with plaque burden and area, respectively.

CONCLUSIONS

Angiographic scoring systems are strongly correlated with each other and with atherosclerotic plaque burden. Scoring systems therefore appear to be a valid estimate of CAD plaque burden.

Measuring myocardial salvage

The efficacy of cardioprotective strategies can be quantified by myocardial salvage as an indicator of therapeutic benefit. Salvage is calculated as the difference between the area at risk (AAR) and the final infarct size (FIS). AAR has been quantified by angiographic assessment followed by quantification of FIS by biochemical ischaemic markers or imaging modalities such as cardiovascular magnetic resonance (CMR). Angiographical methods may overestimate AAR and since methodological differences may exist between different modalities, the use of different modalities for estimating AAR and FIS may not be recommended. (99m)Technetium (Tc)-Sestamibi single-photon emission tomography (SPECT) allows quantification of AAR and FIS by tracer injection prior to revascularization and after 1 month, respectively. SPECT provides the most validated measure of myocardial salvage and has been utilized in multiple randomized clinical trials. However, SPECT is logistically challenging, expensive, and includes radiation exposure. More recently, a large number of studies have suggested that CMR can determine salvage in a single examination by combining measures of myocardial oedema in the AAR exposed to ischaemia reperfusion with FIS quantification by late gadolinium enhancement. The T1- and T2-weighted CMR approaches for quantification of AAR utilize non-contrast, early and late gadolinium enhancement techniques. The technical progress, high spatial resolution and the potential for retrospective quantification of the AAR makes CMR the most appropriate technique for assessment of myocardial salvage. However, the optimum CMR technique for assessment of myocardial AAR remains to be defined. Consequently, we recommend a comprehensive CMR protocol to ensure reliable assessment of myocardial salvage.

Novel QCA methodologies and angiographic scores

Coronary angiography remains the gold-standard method for evaluating coronary artery disease and interventional treatments. As percutaneous coronary interventions have advanced, quantitative coronary angiography (QCA) techniques have also evolved in order to provide more accurate assessments of these therapies. Improvements have been made at each step of the QCA process from image acquisition to vessel analysis. In addition, multiple scoring systems have been developed in order to utilize QCA data, both alone and in conjunction with clinical factors, to better stratify patient risk. This article will review the recent advancements in QCA techniques and outcome prediction models.

Impact of coronary artery disease on outcomes after transcatheter aortic valve implantation

BACKGROUND

Coronary artery disease (CAD) negatively impacts prognosis of patients undergoing surgical aortic valve replacement and revascularization is generally recommended at the time of surgery. Implications of CAD and preprocedural revascularization in the setting of transcatheter aortic valve implantation (TAVI) are not known.

METHOD

Patients who underwent successful TAVI from January 2005 to December 2007 were retrospectively divided into five groups according to the extent of CAD assessed with the Duke Myocardial Jeopardy Score: no CAD, CAD with DMJS 0, 2, 4, and > or =6. Study endpoints included 30-day and 1-year survival, evolution of symptoms, left ventricular ejection fraction (LVEF), and mitral regurgitation (MR) and need of revascularization during follow-up.

RESULTS

One hundred and thirty-six patients were included, among which 104 (76.5%) had coexisting CAD. Thirty-day mortality in the five study groups was respectively 6.3, 14.6, 7.1, 5.6, and 17.7% with no statistically significant difference between groups (P = 0.56). Overall survival rate at one year was 77.9% (95% CL: 70.9, 84.9) with no difference between groups (P = 0.63). Symptoms, LVEF, and MR all significantly improved in the first month after TAVI, but the extent of improvement did not differ between groups (P > 0.08). Revascularization after TAVI was uncommon.

CONCLUSION

The presence of CAD or nonrevascularized myocardium was not associated with an increased risk of adverse events in this initial cohort. On the basis of these early results, complete revascularization may not constitute a prerequisite of TAVI. This conclusion will require re-assessment as experience accrues in patients with extensive CAD.

Comparison between transcatheter and surgical prosthetic valve implantation in patients with severe aortic stenosis and reduced left ventricular ejection fraction

BACKGROUND

Patients with severe aortic stenosis and reduced left ventricular ejection fraction (LVEF) have a poor prognosis with conservative therapy but a high operative mortality when treated surgically. Recently, transcatheter aortic valve implantation (TAVI) has emerged as an alternative to surgical aortic valve replacement (SAVR) for patients considered at high or prohibitive operative risk. The objective of this study was to compare TAVI and SAVR with respect to postoperative recovery of LVEF in patients with severe aortic stenosis and reduced LV systolic function.

METHODS AND RESULTS

Echocardiographic data were prospectively collected before and after the procedure in 200 patients undergoing SAVR and 83 patients undergoing TAVI for severe aortic stenosis (aortic valve area ≤1 cm(2)) with reduced LV systolic function (LVEF ≤50%). TAVI patients were significantly older (81±8 versus 70±10 years; P<0.0001) and had more comorbidities compared with SAVR patients. Despite similar baseline LVEF (34±11% versus 34±10%), TAVI patients had better recovery of LVEF compared with SAVR patients (ΔLVEF, 14±15% versus 7±11%; P=0.005). At the 1-year follow-up, 58% of TAVI patients had a normalization of LVEF (>50%) as opposed to 20% in the SAVR group. On multivariable analysis, female gender (P=0.004), lower LVEF at baseline (P=0.005), absence of atrial fibrillation (P=0.01), TAVI (P=0.007), and larger increase in aortic valve area after the procedure (P=0.01) were independently associated with better recovery of LVEF.

CONCLUSION

In patients with severe aortic stenosis and depressed LV systolic function, TAVI is associated with better LVEF recovery compared with SAVR. TAVI may provide an interesting alternative to SAVR in patients with depressed LV systolic function considered at high surgical risk.

Association of Median Household Income With Burden of Coronary Artery Disease Among Individuals With Diabetes

Background— Low income is associated with adverse cardiovascular outcomes. Diabetes is more prevalent among low income groups, and low income patients with diabetes have been shown to have a greater burden of cardiovascular risk factors and worse cardiovascular outcomes. The objective of this study was to determine whether income status was associated with burden of coronary atherosclerosis in patients with diabetes.

Methods and Results— All patients with diabetes presenting for cardiac catheterization between January 1, 2000, and December 31, 2002, in Calgary, Canada, were identified through the use of the Alberta Provincial Project for Assessing Outcomes in Coronary Heart Disease (APPROACH) database. This clinical database was merged with Canadian 2001 Census data on median household income per dissemination area using patient postal code data, and income quintiles were derived. Clinical profiles, severity of coronary atherosclerosis, and myocardial jeopardy were compared across income quintiles. Mean scores for severity and jeopardy were compared across income quintiles using analysis of variance. Multivariate linear regression was used to control for baseline differences across income groups.

A total of 4596 patients were eligible for inclusion in this study. Clinical profiles differed significantly across income quintiles, with the highest income quintile being younger ( P <0.0005), more likely to be male ( P =0.029), and having a lower prevalence of smoking ( P =0. 039). Low income groups were more likely to report a history of myocardial infarction ( P <0.0005) or congestive heart failure ( P <0.0005). The highest income groups has significantly less coronary atherosclerosis as measured by the weighted Duke index (6.67 versus 7.38, P <0.002), but there were no differences in lesion severity as measured by the Duke severity scale (2.31 versus 2.41, P =0.334). High income patients has significantly less myocardial jeopardy compared with the lowest income group as measured by the Duke and APPROACH scores (36.44 versus 46.23, P =0.0187, and 39.96 versus 45.36, P =0.0182, respectively). These differences remained significant even after controlling for baseline clinical differences in cardiovascular risk factor burden.

Conclusions— Low income is associated with a greater degree of atherosclerosis and greater myocardial jeopardy in patients with diabetes. More needs to be done to reduce cardiovascular risk factor burden in this vulnerable population.

Preoperative and late postoperative mitral regurgitation in ventricular reconstruction: role of local left ventricular deformation

BACKGROUND

We sought to analyze the characteristics of local left ventricular deformation related to functional mitral regurgitation (MR) in post-anterior myocardial infarction scar, and to evaluate how local remodeling contributes to late development of MR after surgical ventricular reconstruction by endoventricular circular patch plasty repair.

METHODS

Two hundred twenty-one consecutive patients (aged 60 +/- 9 years; 193 males) with previous transmural anterior infarction underwent heart catheterization both before and 1 year after endoventricular circular patch plasty repair. Preoperative global left ventricular shape determinants (eccentricity and circularity indexes), regional curvature and wall motion (centerline), and both preoperative and 1-year postoperative hemodynamic parameters (volumes, ejection fraction, capillary wedge and pulmonary artery pressures) were calculated.

RESULTS

Forty-eight patients had (MR patients), and 173 did not have (NoMR patients) angiographic MR grade 2 or more preoperatively; at follow-up, 30 NoMR patients had MR (late MR [LMR]). Before surgery, MR patients had larger left ventricular volumes, higher capillary wedge and mean pulmonary artery pressures, and lower ejection fraction and cardiac index. The LMR patients had similarly high capillary wedge and pulmonary artery pressures as MR patients; otherwise, they did not differ from NoMR patients. Mitral regurgitation patients had wider lateral wall akinesia and greater inferior wall asynergy; the inferobasal region was hypokinetic in LMR patients. In MR patients, inferior wall systolic curvature was less negative; the inferobasal region had a more positive curvature in LMR patients.

CONCLUSIONS

Local deformation of the inferior wall with loss of systolic inward bending is associated with functional MR, while asynergy and systolic deformation of the inferobasal region and high capillary wedge pressure are prognostic signs of MR development late after endoventricular circular patch plasty repair.

Circulating Chlamydia pneumoniae DNA and advanced coronary artery disease

BACKGROUND

Chlamydia pneumoniae (C. pneumoniae) has been linked to atherosclerosis. Detection of this pathogen in peripheral blood cells may be valuable in the diagnosis of disease state. This study aimed to evaluate the prevalence of circulating C. pneumoniae DNA and its relationship with severity and extent of coronary artery disease (CAD).

METHODS

Blood samples from 269 patients undergoing coronary angiography were collected. The presence of circulating C. pneumoniae DNA was determined by real-time PCR assay. Data regarding coronary risk factors and severity and extent of CAD were collected. Severity and extent of CAD was defined by the number of major epicardial coronary arteries with >50% stenosis and by the Duke jeopardy score.

RESULTS

Sixteen of 269 specimens (5.9%) from the study cohort were positive for C. pneumoniae DNA. Thirteen specimens among 149 samples from patients with multi-vessel disease (8.7%) were positive for C. pneumoniae DNA compared with 3 of 120 (2.5%) among patients without multi-vessel CAD. The prevalence of circulating C. pneumoniae DNA was significantly associated with multi-vessel disease. The odds ratio was 5.1 (P=0.02) after adjustment for conventional risk factors.

CONCLUSIONS

Presence of circulating C. pneumoniae DNA is associated with advanced CAD, suggesting C. pneumoniae infection as a contributing factor to progression of coronary atherosclerosis.

Independent contribution of plaque complexity to myocardial ischemia during dobutamine stress echocardiography

The influence of complex plaque morphology on the extent of demand-induced ischemia in unselected patients is not well defined. We sought to investigate the functional significance of lesion morphology in patients who underwent coronary angiography and dobutamine stress echocardiography (DSE). Angiography and DSE were performed within a 6-month period (mean 1 +/- 1 month) in 196 patients. Angiographic assessments involved quantification of stenosis severity, assessment of the extent of jeopardized myocardium, and categorization of plaque morphology according to the Ambrose classification. DSE was interpreted by separate investigators with respect to wall motion score index (WMSI) and number of coronary territories involved. A general linear model was constructed to assess the independent contribution of patient characteristics and angiographic and DSE results with respect to extent of ischemic myocardium. Complex lesion morphology was seen in 62 patients (32%). Patients with complex lesions were more likely to have had prior myocardial infarction (p <0.001) and be current smokers (p = 0.03). During angiography, they exhibited a trend toward a greater number of diseased vessels, had a greater coronary jeopardy score (p <0.001) and more frequent collateral flow (p = 0.03). During echocardiography, patients had a higher stress WMSI (p <0.001) and were more likely to show ischemia in all 3 arterial territories (p <0.01). On multivariate regression, the coronary artery jeopardy score and the presence of complex plaque morphology were independent predictors of the extent of ischemic myocardium (R(2) = 34%, p <0.001). Thus, patients with complex plaque morphology are older, more likely to smoke, and more likely to have had prior myocardial infarction. They exhibit more extensive disease with higher coronary jeopardy scores and a higher resting and peak stress WMSI. Despite these differences, complex plaque morphology remains an independent predictor of the extent of ischemia during stress.

Impact of revascularization and myocardial viability determined by nitrate-enhanced Tc-99m sestamibi and Tl-201 imaging on mortality and functional outcome in ischemic cardiomyopathy

BACKGROUND

Nitrate-enhanced perfusion imaging has been shown to detect viability in dysfunctional myocardium, but nitrate-enhanced technetium 99m sestamibi has not been compared with nitrate-enhanced thallium 201.

METHODS AND RESULTS

Fifty-six patients with ischemic cardiomyopathy and heart failure (New York Heart Association classes II-IV) were scheduled for revascularization. Through use of a matching 12-segment model, nitrate-enhanced Tl-201 and Tc-99m sestamibi uptake at rest was assessed by 2 sets of blinded investigators. All single photon emission computed tomography data sets were read separately. Additional exercise Tc-99m sestamibi single photon emission computed tomography was performed on a separate day. Myocardial viability was thought to be present when the tracer uptake score was less than 3 (normal, 0; absent, 4). Of the 56 patients scheduled to undergo revascularization, only 23 (41%) underwent the procedure and the remainder continued medical therapy. Functional assessment by rest echocardiography was performed at 21 +/- 8 months, and survival was determined at 40 +/- 18 months. The baseline clinical and hemodynamic parameters were similar in the revascularization (n = 23) and medical therapy (n = 33) groups. Perfusion scores with nitrate-enhanced Tl-201 and Tc-99m sestamibi were similar in dysfunctional segments. Stress Tc-99m sestamibi reversible defects predicted significant improvement in left ventricular function compared with those without defects (P <.01) after revascularization. Cox regression model showed that when at least 5 reversible segments were viable, revascularization produced greater improvements in New York Heart Association class, a better trend toward survival (P =.07 for Tl-201 and P =.06 for Tc-99m), and a significantly greater impact on reverse remodeling.

CONCLUSIONS

Myocardial viability determined by nitrate-enhanced Tl-201 and myocardial viability determined by Tc-99m sestamibi are equivalent for predicting functional improvements, remodeling, and survival after revascularization in patients with ischemic cardiomyopathy.

Validation of three myocardial jeopardy scores in a population-based cardiac catheterization cohort

BACKGROUND

The Jeopardy Score from Duke University and the Myocardial Jeopardy Index from the Bypass Angioplasty Revascularization Investigation (BARI) have been validated but never applied to a large unselected cohort. We assessed the prognostic value of these existing jeopardy scores, along with that of a new Lesion Score developed for the Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease (APPROACH), a clinical data collection initiative capturing all patients undergoing cardiac catheterization in the province of Alberta.

METHODS

The predictive value of these three scores were compared in a cohort of >20,000 patients (9922 treated medically, 6334 treated with percutaneous intervention, and 3811 treated with bypass surgery). Scores were considered individually in logistic regression models for their ability to predict outcome and then added to models containing sociodemographic data, comorbidities, ejection fraction, indication for procedure, and descriptors of coronary anatomy.

RESULTS

All scores were found to be predictive of 1-year mortality, especially when patients are treated medically or with percutaneous intervention. In these patients, the APPROACH Lesion Score performed slightly better than the other jeopardy scores. The Duke Jeopardy Score was most predictive in those patients undergoing coronary bypass surgery.

CONCLUSIONS

Myocardial jeopardy scores provide independent prognostic information for patients with ischemic heart disease, especially if those patients are treated medically or with percutaneous intervention. These scores represent potentially valuable tools in cardiovascular outcome studies. The APPROACH Lesion Score may perform slightly better than previously developed jeopardy scores.

Myocardial viability on echocardiography predicts long-term survival after revascularization in patients with ischemic congestive heart failure

OBJECTIVES

This study was conducted to evaluate the effect of revascularization on survival in patients with congestive heart failure (CHF) due to ischemic left ventricular (LV) systolic dysfunction based on the presence of myocardial viability (MV).

BACKGROUND

There are insufficient data regarding the survival benefit of revascularization in patients with CHF due to ischemic LV systolic dysfunction.

METHODS

Follow-up was obtained in 87 consecutive patients with CHF due to ischemic LV systolic dysfunction (New York Heart Association [NYHA] class II-IV; LV ejection fraction <0.35) who underwent low-dose dobutamine echocardiography (DE). MV within each of 12 myocardial segments representing the LV was defined as having either: 1) normal function or mild dyssynergy at rest; 2) severe resting dyssynergy that improved on DE, or 3) worsening of function on DE except in the case of akinesia.

RESULTS

At a mean follow-up of 40+/-17 months, 37 patients had received revascularization on the basis of clinical grounds, and there were 22 (25%) cardiac-related deaths. Multivariate Cox regression analysis revealed that when patients with at least five segments showing MV underwent revascularization, mortality was reduced by an average of 93% (confidence interval of 22% to 99%), which was associated with improvement in NYHA class as well as LV ejection fraction. Patients with less than five segments showing MV who underwent revascularization (and thus, showing mostly scar), and those with at least 5 segments demonstrating MV who were treated medically, had a much higher mortality.

CONCLUSIONS

Revascularization produces a clear survival benefit in patients with CHF due to ischemic LV systolic dysfunction who have a significant region of the LV demonstrating MV. These data may have wide-ranging implications in the management of patients with coronary artery disease whose main clinical presentation is CHF.

Paracrine coronary endothelial control of left ventricular function in humans

BACKGROUND

Similar to endothelial modulation of vascular tone, myocardial contraction may be modulated by cardioactive agents released from the coronary endothelium. To investigate such modulation in humans, we performed invasive assessment of left ventricular (LV) function before, during, and after bicoronary infusion of substance P, which releases nitric oxide from the endothelium.

METHODS AND RESULTS

Eight healthy subjects were investigated during diagnostic coronary angiography and eight transplant recipients during annual catheterization. Tip-micromanometer LV pressure was recorded before, during, and after bicoronary (n = 16) and right atrial (n = 14) infusion of substance P (20 pmol/min). LV angiograms (n = 11) were obtained before and at the end of the substance P infusion. At the end of the intracoronary substance P infusion, we observed (1) a fall in LV peak systolic pressure from 147 +/- 16 to 139 +/- 15 mm Hg (P < .01) in healthy subjects and from 147 +/- 25 to 141 +/- 22 mmHg (P < .05) in transplant recipients; (2) a downward and rightward shift of the average LV end-systolic pressure-volume point consistent with depressed systolic performance; and (3) a rise in LV end-diastolic volume at comparable end-diastolic pressure, consistent with increased end-diastolic distensibility. Five minutes after the substance P infusion, LV peak systolic pressure was higher than at baseline in healthy subjects (154 +/- 18 mm Hg; P < .05). Right atrial infusion of substance P did not reproduce these changes.

CONCLUSIONS

Bicoronary infusion of substance P modulates LV function in humans, probably through paracrine myocardial action of cardioactive agents released from the coronary endothelium.

Ischemic cardiomyopathy without significant coronary stenosis. A case report

The authors present a rare case of myocardial infarction in a fifty-eight-year-old man without significant coronary artery stenosis apparent on the emergency coronary angiogram. However, a second angiogram two days later revealed a total occlusion of the left anterior descending artery. Intracoronary thrombolytic therapy was performed with a successful outcome. The patient was subsequently readmitted with an acute myocardial infarction, and the coronary angiogram again failed to demonstrate significant stenosis. Thereafter, the patient's left ventricular function deteriorated progressively, with the occurrence of another myocardial infarction and frequent bouts of symptoms related to congestive heart failure. He died of ischemic cardiomyopathy about seven years later. Findings including an autopsy report showed that myocardial ischemia was involved in the pathogenesis of what initially appeared to be primary dilated cardiomyopathy, based on emergency angiograms.

Significance of ST segment depression during adenosine-induced coronary hyperemia in angina pectoris and correlation with angiographic, scintigraphic, hemodynamic, and echocardiographic variables

Factors determining myocardial ischemia during adenosine-induced coronary vasodilation in patients with angina pectoris are not well defined. To evaluate the angiographic, scintigraphic, hemodynamic, and echocardiographic determinants of ST segment depression during adenosine infusion, 40 patients with angina pectoris underwent technetium-99m sestamibi single photon emission computed tomography and simultaneous two-dimensional echocardiography. Ischemic ST depression occurred in 18 patients (45%). Coronary angiography was performed in all patients and a coronary artery jeopardy score was determined. The sensitivity, specificity, and the predictive accuracy of adenosine-induced ST segment depression in detecting significant coronary artery disease were 53%, 100%, and 60%, respectively, while the corresponding results for detecting reversible perfusion defects were 61%, 92%, and 70%, respectively. Univariate predictors of ST segment depression included the coronary artery jeopardy score, the presence and the extent of reversible perfusion defects, the presence of three-vessel and/or left main coronary artery disease, and diastolic blood pressure at peak adenosine infusion. There was a trend (P = 0.06) to a higher incidence of collateral vessels in patients developing ST segment depression. The coronary artery jeopardy score was found to be the only significant independent predictor of ST segment depression by stepwise multivariate logistic regression analysis. Thus, in patients with angina pectoris, the coronary artery jeopardy score, representing the extent of significant coronary artery disease, is the most important independent predictor of adenosine-induced ST segment depression. ST depression is unusual in the absence of reversible perfusion defects and is also associated with more extensive reversible defects.

Acute effects of nitric oxide on left ventricular relaxation and diastolic distensibility in humans. Assessment by bicoronary sodium nitroprusside infusion

BACKGROUND

In isolated mammalian cardiomyocytes, papillary muscle preparations, and ejecting hearts, nitric oxide (NO) or other cyclic GMP-elevating interventions increase diastolic cell length and reduce peak contractile performance by hastening onset of myocardial relaxation. In the present study, the effect of NO on left ventricular (LV) relaxation and diastolic distensibility was investigated in humans.

METHODS AND RESULTS

The NO donor substance sodium nitroprusside was infused during cardiac catheterization in the global coronary bed of the LV of patients (n = 13) investigated for chest pain who were without evidence of obstructive coronary artery or other cardiac disease. Sodium nitroprusside was infused intracoronarily at a dosage (< or = 4 micrograms/min) that was previously shown to be devoid of systemic effects when infused into the brachial artery to investigate the reactivity of the forearm vascular bed. The effect of this global intracoronary infusion of the NO donor sodium nitroprusside was assessed by sequential LV angiograms and tip-micromanometer pressure recordings. During global intracoronary nitroprusside infusion, there was a decrease in heart rate from 78 +/- 11 to 76 +/- 12 beats per minute (P < .05), in LV peak systolic pressure from 161 +/- 18 to 146 +/- 18 mm Hg (P < .001), and in time to onset of LV relaxation (interval from Q wave on the ECG to LV dP/dtmin) from 432 +/- 36 to 419 +/- 36 milliseconds (P < .01). In 7 patients in whom adequate sequential LV angiograms could be obtained, LV end-diastolic volume increased from 158 +/- 34 to 165 +/- 40 mL (P < .05), whereas LV end-diastolic pressure fell from 18 +/- 5 to 12 +/- 3 mm Hg (P < .02), and in 5 of these 7 patients, a downward shift of the diastolic LV pressure-volume relation was observed. In 5 patients, a right atrial infusion of sodium nitroprusside was performed either before (n = 2) or after the global intracoronary infusion. The decrease in LV peak systolic pressure observed during right atrial infusion was significantly smaller (P < .01) than during global intracoronary infusion.

CONCLUSIONS

The present study reveals reduced LV pressure development, an LV relaxation-hastening effect, and improved LV diastolic distensibility during global intracoronary infusion of the NO donor substance sodium nitroprusside. These effects appeared to be unrelated to systemic vasodilation or to pericardial constraint and could be explained by a direct myocardial effect of NO, probably through activation of guanylyl cyclase to increase cyclic GMP or through modification of other cellular proteins.

Myocardial risk area defined by technetium-99m sestamibi imaging during percutaneous transluminal coronary angioplasty: comparison with coronary angiography

OBJECTIVES

The purpose of this study was to compare the assessment of myocardial area at risk in patients with coronary artery stenosis by coronary angiography and quantitative myocardial perfusion imaging with technetium-99m sestamibi.

BACKGROUND

Decisions concerning patient management frequently rely on semiquantitative angiographic estimation of the myocardial area at risk, although this approach has not been well validated. Technetium-99m sestamibi is a perfusion imaging agent with little redistribution after initial myocardial uptake. This characteristic allows for injection during angioplasty and later imaging for visualization and quantitation of the nonperfused area at risk.

METHODS

Thirty-nine patients referred for coronary angioplasty were studied. Technetium-99m sestamibi was injected intravenously during angioplasty balloon inflation. Planar (33 patients) or tomographic (6 patients) imaging was performed after completion of angioplasty. Imaging was repeated 24 to 48 h later. Myocardial risk area (perfusion defect on angioplasty image) was quantified as an integral using circumferential count distribution profiles and normal reference. Angiographic risk area was assessed using five scoring methods.

RESULTS

The scintigraphic risk area was 14 +/- 15 on planar images and 39 +/- 16 on tomography. Scintigraphic risk area of patients with infarction was larger than in patients without (22 +/- 17 versus 7 +/- 8, p = 0.003). The left anterior descending coronary artery had a larger mean risk area than other vessels (22 +/- 15 versus 7 +/- 11, p = 0.002). The presence of angiographic collateral channels was associated with smaller risk areas. Angiographic risk scores correlated only moderately with the technetium-99m sestamibi risk area (r = 0.54 to 0.65), with considerable spread of data.

CONCLUSIONS

Area at risk estimated from coronary angiography does not correlate well with that from quantitative myocardial perfusion imaging with technetium-99m sestamibi. These findings emphasize that the functional significance of coronary artery disease is not predicted by coronary anatomy alone.

Ischemic cardiomyopathy: endomyocardial biopsy and ventriculographic evaluation of patients with congestive heart failure, dilated cardiomyopathy and coronary artery disease

OBJECTIVES

This study was designed to define clinical and pathophysiologic similarities and differences between patients with ischemic and idiopathic dilated cardiomyopathy.

BACKGROUND

Significant coronary artery disease in patients with new onset congestive heart failure due to dilated cardiomyopathy has important prognostic and therapeutic implications.

METHODS

Clinical, histologic, ventriculographic and hemodynamic features of patients with dilated cardiomyopathy who underwent coronary angiography were reviewed.

RESULTS

Patients with ischemic cardiomyopathy (n = 21) compared with those with idiopathic cardiomyopathy (n = 40) had similar presenting symptoms, durations of illness, and coronary risk factor profiles, with the exception of a greater prevalence of cigarette smoking (71% vs. 39%, p = 0.028) and male gender (100% vs. 70%, p = 0.014). Endomyocardial biopsy specimens from patients with ischemic cardiomyopathy demonstrated a greater prevalence of replacement fibrosis (48% vs. 8%, p = 0.001) and a lesser degree of histologically assessed myocyte hypertrophy (mean grade 0.5 +/- 0.7 vs. 1.3 +/- 1.3, p = 0.015). Although ventriculographically determined regional dyskinesia was present in both groups, there was a higher prevalence of two or more adjacent segments in the ischemic cardiomyopathy group (50% vs. 10%, p = 0.03). This ischemic group had hemodynamic variables associated with a worse prognosis: higher pulmonary artery wedge pressure (23 +/- 10 vs. 15 +/- 9 mm Hg, p = 0.006) and lower cardiac index (2.0 +/- 0.5 vs. 2.3 +/- 0.5 liters/min per m2, p = 0.044). Also, in this group, patients had a mean of 2.6 +/- 0.7 diseased vessels; 15 (71%) of 21 patients had triple-vessel disease and 18 (86%) of 21 had at least one occluded or suboccluded artery.

CONCLUSIONS

1) Patients with ischemic and idiopathic cardiomyopathy may be clinically indistinguishable unless coronary angiography is performed. 2) A greater prevalence of replacement fibrosis and a lesser degree of myocardial hypertrophy in patients with ischemic cardiomyopathy may account for the greater extent of hemodynamic decompensation observed at presentation.

Distinguishing ischemic cardiomyopathy from nonischemic dilated cardiomyopathy with coronary echocardiography

Transthoracic echocardiographic examination of the proximal left coronary system was performed in 59 patients who had dilated cardiomyopathy to determine if this technique could distinguish between ischemic and nonischemic dilated cardiomyopathy. With use of annular array transducers (3.5 or 5 MHz) and digital image processing, echocardiographic visualization of the coronary arteries was successful in 55 (93%) of 59 patients. As assessed by coronary angiography, 32 subjects had ischemic cardiomyopathy and 27 had nonischemic cardiomyopathy. Twenty-seven (84%) of the 32 patients who had coronary artery disease and 24 (89%) of the 27 patients with nonischemic cardiomyopathy were correctly identified. The accuracy of coronary echocardiography was 86% in the entire study group and 93% when patients with inadequate studies were excluded. All subjects who had ischemic cardiomyopathy had evidence of disease by coronary echocardiography or segmental wall motion abnormalities. Multivariate analysis permitted correct classification of 93% of all subjects based on the results of the coronary echocardiogram, evaluation of segmental wall motion and a history of prior myocardial infarction. The correct diagnosis was made in 86% when the results of coronary echocardiography were excluded from analysis using all other echocardiographic and clinical variables. Transthoracic coronary echocardiography can be performed with a high degree of success in patients with dilated ventricles and the technique can reliably distinguish between ischemic and nonischemic dilated cardiomyopathy.