Diagnostic accuracy of 64-slice computed tomography coronary angiography in a large population of patients without revascularisation: registry data on the impact of calcium score

Purpose

This study evaluated the diagnostic accuracy of computed tomography coronary angiography (CTCA) for detecting significant coronary artery stenosis (??50% lumen reduction) at different coronary calcium score (CACS) values with conventional coronary angiography (CAG) as the reference standard.

Material and methods

A total of 1,500 patients (928 men, mean age 58.2??12.5 years) in sinus rhythm who underwent CTCA (64-slice technology) and CAG were enrolled. Diagnostic accuracy and likelihood ratios (LR) of CTCA were evaluated against CAG for the total population and in different CACS classes (0; 1?C10; 11?C100; 101?C400; 401?C1,000; >1,000).

Results

The prevalence of obstructive disease was 51% (23.5% single vessel; 27.5% multivessel; progressive increase from 17.9% to 94% through the CACS classes). In the per-patient analysis, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of CTCA were 99%, 92%, 94% and 99%, respectively. Per-patient analysis showed a worse PPV of CTCA (76?C77%) in classes with low CACS (1?C10/11?C100). Per-patient LR were higher in classes with extreme CACS values (0 = LR+ 18.3 and LR? = 0.0; c1,000 = LR+ 17.0 and LR? = 0.0) with values always >7 for LR+ and <0.033 for LR? for all CACS classes.

Conclusions

CTCA is a reliable diagnostic modality, with high sensitivity and NPV regardless of CACS.     

Diagnostic accuracy of 64-slice computed tomography coronary angiography in a large population of patients without revascularisation: registry data in NSTEMI acute coronary syndrome and influence of gender and risk factors

Purpose

This study sought to evaluate the diagnostic accuracy of computed tomography coronary angiography (CTCA) for detecting significant coronary artery stenosis (??50% lumen reduction) compared with conventional coronary angiography (CAG) in non-ST-elevation myocardial infarction-acute coronary syndrome (NSTEMI-ACS) and in subgroups selected by gender and number of risk factors (RF).

Materials and methods

We selected from a population of 1,500 patients in a multicentre registry with NSTEMI-ACS who had undergone CTCA and CAG, (n=237; 187 men, mean age 63±10 years). Diagnostic accuracy and likelihood ratios (LR) of CTCA were assessed against CAG in the total population and subgroups (men, women: 0 RF = absence of RF, 1?C2 RF = presence of one or two RF, >2 RF = presence of more than two RF).

Results

The prevalence of obstructive disease was 53%. In the per-patient analysis, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of CTCA were 100% (men 100%; women 100%; 0 RF 100%; 1?C2 RF 100%; >2 RF 100%), 95% (men 98%; women 50%; 0 RF NA% (NA, not assessable); 1?C2 RF 96%; >2 RF 96%), 95% (men 98%; women 91%; 0 RF 91%; 1?C2 RF 96%; >2 RF 96%), 100% (men 100%; women 100%; 0 RF NV%; 1?C2 RF 100%; >2 RF 100%), respectively. The per-segment analysis showed a reduction in PPV (ranging between 56% and 67%). The per-patient LR+ ranged between 18 and 27, whereas LR-were always 0. We observed no significant differences in diagnostic accuracy between subgroups.

Conclusions

CTCA is a reliable diagnostic modality with high sensitivity and NPV in NSTEMI-ACS patients who are not candidates for early revascularisation, regardless of gender and number of risk factors.     

Diagnostic accuracy of 64-slice computed tomography coronary angiography in a large population of patients without revascularisation: registry data and review of multicentre trials

Purpose

This study was undertaken to evaluate the diagnostic accuracy of computed tomography coronary angiography (CT-CA) for the detection of significant coronary artery stenosis (≥50% lumen reduction) compared with conventional coronary angiography (CCA) in a registry and to review major multicentre trials.

Materials and methods

A total of 1,372 patients (882 men, 490 women; mean age 59.3±11.9 years) in sinus rhythm were studied with CT-CA (64-slice technology) and CCA. The diagnostic accuracy of CT-CA was evaluated against quantitative CCA as a reference standard for coronary artery stenosis. Positive and negative likelihood ratios and inter- and intraobserver agreement were calculated.

Results

The prevalence of disease was 53%. CCA demonstrated the absence of significant coronary artery disease in 46.6% (639/1372), single-vessel disease in 24.7% (337/1372) and multivessel disease in 28.9% (396/1372) of patients. In per-patient analysis sensitivity, specificity and positive and negative predictive value of CT-CA were 99% [confidence interval (CI) 97–99], 92% (CI 89–94), 94% (CI 91–95) and 99% (CI 97–99), respectively. Per-patient and per-segment likelihood ratios (LR+=12.4 and LR?=0.011; LR+=18.3 and LR?=0.064, respectively), were good. Inter- and intraobserver variability was 0.78 and 0.85, respectively.

Conclusions

CT-CA is a reliable diagnostic modality both in terms of sensitivity and negative predictive value. Differences in trial results are also due to the different parameters used for patient inclusion.     

Stress-ECG vs. CT coronary angiography for the diagnosis of coronary artery disease: a “real-world” experience

Purpose

This study aimed to evaluate the diagnostic accuracy of stress electrocardiogram (ECG) and computed tomography coronary angiography (CTCA) for the detection of significant coronary artery stenosis (≥50%) in the real world using conventional CA as the reference standard.

Materials and methods

A total of 236 consecutive patients (159 men, 77 women; mean age 62.8±10.2 years) at moderate risk and with suspected coronary artery disease (CAD) were enrolled in the study and underwent stress ECG, CTCA and CA. The CTCA scan was performed after i.v. administration of a 100-ml bolus of iodinated contrast material. The stress ECG and CTCA reports were used to evaluate diagnostic accuracy compared with CA in the detection of significant stenosis ≥50%.

Results

We excluded 16 patients from the analysis because of the nondiagnostic quality of stress ECG and/or CTCA. The prevalence of disease demonstrated at CA was 62% (n=220), 51% in the population with comparable stress ECG and CTCA (n=147) and 84% in the population with equivocal stress ECG (n=73). Stress ECG was classified as equivocal in 73 cases (33.2%), positive in 69 (31.4%) and negative in 78 (35.5%). In the per-patient analysis, the diagnostic accuracy of stress ECG was sensitivity 47%, specificity 53%, positive predictive value (PPV) 51% and negative predictive value (NPV) 49%. On stress ECG, 40 (27.2%) patients were misclassified as negative, and 34 (23.1%) patients with nonsignificant stenosis were overestimated as positive. The diagnostic accuracy of CTCA was sensitivity 96%, specificity 65%, PPV 74% and NPV 94%. CTCA incorrectly classified three (2%) as negative and 25 (17%) as positive. The difference in diagnostic accuracy between stress ECG and CTCA was significant (p<0.01).

Conclusions

CTCA in the real world has significantly higher diagnostic accuracy compared with stress ECG and could be used as a first-line study in patients at moderate risk.     

Computed tomography coronary angiography accuracy in women and men at low to intermediate risk of coronary artery disease

Objectives

To investigate the diagnostic accuracy of CT coronary angiography (CTCA) in women at low to intermediate pre-test probability of coronary artery disease (CAD) compared with men.

Methods

In this retrospective study we included symptomatic patients with low to intermediate risk who underwent both invasive coronary angiography and CTCA. Exclusion criteria were previous revascularisation or myocardial infarction. The pre-test probability of CAD was estimated using the Duke risk score. Thresholds of less than 30?% and 30–90?% were used for determining low and intermediate risk, respectively. The diagnostic accuracy of CTCA in detecting obstructive CAD (≥50?% lumen diameter narrowing) was calculated on patient level. P?<?0.05 was considered significant.

Results

A total of 570 patients (46?% women [262/570]) were included and stratified as low (women 73?% [80/109]) and intermediate risk (women 39?% [182/461]). Sensitivity, specificity, PPV and NPV were not significantly different in and between women and men at low and intermediate risk. For women vs. men at low risk they were 97?% vs. 100?%, 79?% vs. 90?%, 80?% vs. 80?% and 97?% vs. 100?%, respectively. For intermediate risk they were 99?% vs. 99?%, 72?% vs. 83?%, 88?% vs. 93?% and 98?% vs. 99?%, respectively.

Conclusion

CTCA has similar diagnostic accuracy in women and men at low and intermediate risk.

Key Points

? Coronary artery disease (CAD) is increasingly investigated by computed tomography angiography (CTCA). ? CAD detection or exclusion by CTCA is not different between sexes. ? CTCA diagnostic accuracy was similar between low and intermediate risk sex-specific-groups. ? CTCA rarely misses obstructive CAD in low–intermediate risk women and men. ? CAD yield by invasive coronary angiography after positive CTCA is similar between sex-risk-specific groups.     

Diagnostic accuracy of second-generation dual-source computed tomography coronary angiography with iterative reconstructions: a real-world experience

Purpose

The authors evaluated the diagnostic accuracy of second-generation dual-source (DSCT) computed tomography coronary angiography (CTCA) with iterative reconstructions for detecting obstructive coronary artery disease (CAD).

Materials and methods

Between June 2010 and February 2011, we enrolled 160 patients (85 men; mean age 61.2±11.6 years) with suspected CAD. All patients underwent CTCA and conventional coronary angiography (CCA). For the CTCA scan (Definition Flash, Siemens), we use prospective tube current modulation and 70-100 ml of iodinated contrast material (Iomeprol 400 mgI/ ml, Bracco). Data sets were reconstructed with iterative reconstruction algorithm (IRIS, Siemens). CTCA and CCA reports were used to evaluate accuracy using the threshold for significant stenosis at ??50% and ??70%, respectively.

Results

No patient was excluded from the analysis. Heart rate was 64.3±11.9 bpm and radiation dose was 7.2±2.1 mSv. Disease prevalence was 30% (48/160). Sensitivity, specificity and positive and negative predictive values of CTCA in detecting significant stenosis were 90.1%, 93.3%, 53.2% and 99.1% (per segment), 97.5%, 91.2%, 61.4% and 99.6% (per vessel) and 100%, 83%, 71.6% and 100% (per patient), respectively. Positive and negative likelihood ratios at the per-patient level were 5.89 and 0.0, respectively.

Conclusions

CTCA with second-generation DSCT in the real clinical world shows a diagnostic performance comparable with previously reported validation studies. The excellent negative predictive value and likelihood ratio make CTCA a first-line noninvasive method for diagnosing obstructive CAD.     

Coronary calcium score and computed tomography coronary angiography in high-risk asymptomatic subjects: assessment of diagnostic accuracy and prevalence of non-obstructive coronary artery disease

Objectives

The aim of the study was to compare the coronary artery calcium score (CACS) and computed tomography coronary angiography (CTCA) for the assessment of non-obstructive/obstructive coronary artery disease (CAD) in high-risk asymptomatic subjects.

Methods

Two hundred and thirteen consecutive asymptomatic subjects (113 male; mean age 53.6?±?12.4 years) with more than one risk factor and an inconclusive or unfeasible non-invasive stress test result underwent CACS and CTCA in an outpatient setting. All patients underwent conventional coronary angiography (CAG). Data from CACS (threshold for positive image: Agatston score 1/100/1,000) and CTCA were compared with CAG regarding the degree of CAD (non-obstructive/obstructive; </≥50% lumen reduction).

Results

The mean calcium score was 151?±?403 and the prevalence of obstructive CAD was 17% (8% one-vessel and 10% two-vessel disease). Per-patient sensitivity, specificity, positive and negative predictive values of CACS were: 97%, 75%, 45%, and 100%, respectively (Agatston?≥1); 73%, 90%, 60%, and 94%, respectively (Agatston?≥100); 30%, 98%, 79%, and 87%, respectively (Agatston?≥1,000). Per-patient values for CTCA were 100%, 98%, 97%, and 100%, respectively (p?<?0.05). CTCA detected 65% prevalence of all CAD (48% non-obstructive), while CACS detected 37% prevalence of all CAD (21% non-obstructive) (p?<?0.05).

Conclusion

CACS proved inadequate for the detection of obstructive and non-obstructive CAD compared with CTCA. CTCA has a high diagnostic accuracy for the detection of non-obstructive and obstructive CAD in high-risk asymptomatic patients with inconclusive or unfeasible stress test results.     

Diagnostic accuracy of 128-slice dual-source CT coronary angiography: a randomized comparison of different acquisition protocols

Objectives

To compare the diagnostic performance and radiation exposure of 128-slice dual-source CT coronary angiography (CTCA) protocols to detect coronary stenosis with more than 50 % lumen obstruction.

Methods

We prospectively included 459 symptomatic patients referred for CTCA. Patients were randomized between high-pitch spiral vs. narrow-window sequential CTCA protocols (heart rate below 65 bpm, group A), or between wide-window sequential vs. retrospective spiral protocols (heart rate above 65 bpm, group B). Diagnostic performance of CTCA was compared with quantitative coronary angiography in 267 patients.

Results

In group A (231 patients, 146 men, mean heart rate 58?±?7 bpm), high-pitch spiral CTCA yielded a lower per-segment sensitivity compared to sequential CTCA (89 % vs. 97 %, P?=?0.01). Specificity, PPV and NPV were comparable (95 %, 62 %, 99 % vs. 96 %, 73 %, 100 %, P?>?0.05) but radiation dose was lower (1.16?±?0.60 vs. 3.82?±?1.65 mSv, P?<?0.001). In group B (228 patients, 132 men, mean heart rate 75?±?11 bpm), per-segment sensitivity, specificity, PPV and NPV were comparable (94 %, 95 %, 67 %, 99 % vs. 92 %, 95 %, 66 %, 99 %, P?>?0.05). Radiation dose of sequential CTCA was lower compared to retrospective CTCA (6.12?±?2.58 vs. 8.13?±?4.52 mSv, P?<?0.001). Diagnostic performance was comparable in both groups.

Conclusion

Sequential CTCA should be used in patients with regular heart rates using 128-slice dual-source CT, providing optimal diagnostic accuracy with as low as reasonably achievable (ALARA) radiation dose.

Key Points

? 128-slice dual-source CT coronary angiography offers several different acquisition protocols. ? Randomized comparison of protocols reveals an optimal protocol selection strategy. ? Appropriate CTCA protocol selection lowers radiation dose, while maintaining high quality. ? CTCA protocol selection should be based on individual patient characteristics. ? A prospective sequential protocol is preferred for CTCA.     

Computed tomography coronary angiography in the selection of outlier patients: a feasibility report

Purpose

This study evaluated criteria, presence and distribution of outlier patients by means of computed tomography coronary angiography (CTCA) in a large institutional database.

Material and methods

From a population of 2,881 consecutive patients (1,842 men, mean age 62±13 years) in sinus rhythm who underwent CTCA, we extracted data on patients with suspected coronary artery disease (CAD). We selected patient outliers in the fifth and sixth decades of life with the following criteria: ??3 risk factors and absence of CAD, zero to one risk factors and ??5 diseased coronary segments. Diabetes was excluded from risk factors because of the different impact on CAD.

Results

The patient population consisted of 2,432 individuals with suspected CAD (1,495 men, age 62±13 years). The prevalence of obstructive CAD (??50% lumen reduction at CTCA) was 36% (863/2,432). Patients with normal coronary arteries accounted for 34% of the total (837/2,432; 431 men, age 55±14 years). Of these, 210 were in the fifth and 231 in the 6th decade (men 196, women 245); those with ??3 risk factors accounted for 4.2% of the total (102/2,432; men 42, women 60). Patients with ??5 diseased coronary segments accounted for 28% of the total (686/2,432; 510 men, age 68±10 years). Of these, 115 were in the fifth and 270 in the sixth decade (men 309, women 76); those with zero to one risk factors accounted for 3.0% (73/2,432; men 66, women 7).

Conclusions

CTCA is a reliable noninvasive diagnostic modality that can be used to identify outlier patients. This will enable dedicated trials aimed at characterising biomarkers and genomics of protective and nonprotective factors against CAD and its complications.     

Computed tomography coronary angiography in asymptomatic patients

Purpose

This study assessed the accuracy of computed tomography coronary angiography (CT-CA) for detecting significant coronary artery disease (CAD; ??50% lumen reduction) in intermediate/high-risk asymptomatic patients.

Materials and methods

A total of 183 consecutive asymptomatic individuals (92 men; mean age 54??11 years) with more than one major risk factor (obesity, hypertension, diabetes, hypercholesterolaemia, family history, smoking) and an inconclusive or nonfeasible noninvasive stress test result (stress electrocardiography, stress echocardiography, nuclear stress scintigraphy) underwent CT-CA in an outpatient setting. All patients underwent conventional coronary angiography (CAG) within 4 weeks. Data from CT-CA were compared with CAG regarding the presence of significant CAD (??50% lumen reduction).

Results

Mean calcium score was 177??432, mean heart rate during the CT-CA scan was 58??8 bpm and the prevalence (per-patient) of obstructive CAD was 19%. CT-CA showed single-vessel CAD in 9% of patients, two-vessel CAD in 9% and three-vessel CAD in 0%. Per-patient sensitivity, specificity, positive predictive value and negative predictive value of CT-CA were 100% (90?C100), 98% (96?C99), 97% (85?C99), 100% (97?C100), respectively. Positive and negative likelihood ratios were 151 and 0, respectively.

Conclusions

CT-CA is an excellent noninvasive imaging modality for excluding significant CAD in intermediate/ high-risk asymptomatic patients with inconclusive or nonfeasible noninvasive stress test.     

Assessment of coronary artery disease and calcified coronary plaque burden by computed tomography in patients with and without diabetes mellitus

Purpose

To compare the coronary atherosclerotic burden in patients with and without type-2 diabetes using CT Coronary Angiography (CTCA).

Methods and Materials

147 diabetic (mean age: 65?±?10?years; male: 89) and 979 nondiabetic patients (mean age: 61?±?13?years; male: 567) without a history of coronary artery disease (CAD) underwent CTCA. The per-patient number of diseased coronary segments was determined and each diseased segment was classified as showing obstructive lesion (luminal narrowing >50%) or not. Coronary calcium scoring (CCS) was assessed too.

Results

Diabetics showed a higher number of diseased segments (4.1?±?4.2 vs. 2.1?±?3.0; p??400 (p?p?p?p?=?0.003) and obstructive CAD (12.5% vs. 3.8%, p?=?0.01). Among patients with CCS????10 all diabetics with obstructive CAD had a zero CCS and one patient was asymptomatic.

Conclusions

Diabetes was associated with higher coronary plaque burden. The present study demonstrates that the absence of coronary calcification does not exclude obstructive CAD especially in diabetics.     

Prognostic value of CT coronary angiography: focus on obstructive vs. nonobstructive disease and on the presence of left main disease

Purpose

The authors investigated the prognostic value of computed tomography coronary angiography (CTCA) for major adverse cardiac events (MACE) in patients with suspected or known coronary artery disease (CAD), with particular focus on left main (LM) disease and obstructive vs. nonobstructive disease.

Materials and methods

A total of 727 consecutive patients (485 men, age 62±11years) with suspected (514; 70.1%) or known (213; 29.9%) CAD underwent CTCA. Patients were followed up for the occurrence of MACE (i.e. cardiac death, nonfatal myocardial infarction, unstable angina, percutaneous/surgical revascularisation).

Results

A total of 117 MACE [five cardiac deaths, 11 acute myocardial infarctions (AMI), five unstable angina, 86 percutaneous coronary interventions, ten coronary artery bypass grafts] occurred during a mean follow-up of 20 months. Severity and extension of CAD was associated with a progressively worse prognosis. The event rate was 0% among patients with normal coronary arteries at CTCA. The presence of LM disease was not associated with a worse prognosis either in patients with no history of CAD or in those with a history of CAD. At multivariate analysis, presence of obstructive CAD and diabetes were the only independent predictors of MACE.

Conclusions

Evaluation of atherosclerotic burden by CTCA provides an independent prognostic value for prediction of MACE. Patients with normal CTCA findings have an excellent prognosis at follow-up.     

Prospective evaluation of magnetic resonance enterography for the detection of mesenteric small bowel tumours

Purpose

To prospectively evaluate magnetic resonance (MR) enterography for detecting mesenteric small-bowel tumours (MSBTs) and assess the added value of gadolinium-chelate injection.

Material and methods

Over a 2-year period MR enterography examinations of 75 patients (33 men, 42 women; mean age, 53.8 years; range, 19–85) with suspected MSBT were blindly analysed by two readers for the presence of MSBT. Sensitivities, specificities, predictive positive values (PPVs), negative predictive values (NPVs) and accuracies of MR enterography for the detection of MSBT were calculated on per-patient and per-lesion bases. The McNemar test was used to compare sensitivities and specificities of the unenhanced and gadolinium-enhanced sets of MR enterographies.

Results

Thirty-seven MSBTs were pathologically confirmed in 26 patients. The mean tolerance score of the examinations was 0.7. On a per-patient basis, sensitivity, specificity, PPV, NPV and accuracy for detection of MSBT were 96 % [95 % CI, 89–100 %], 96 % [90–100 %], 93 % [83–100 %], 98 % [94–100 %] and 96 % [92–100 %], respectively. On a per-lesion basis, sensitivity and PPV were 70 % [56–85 %] and 93 % [83–100 %], respectively. Gadolinium injection yielded higher sensitivities on both bases (P?=?0.008).

Conclusion

MR enterography is an accurate and well-tolerated imaging modality for detecting MSBT. Intravenous administration of gadolinium-chelate improves sensitivity for MSBT detection.

Key Points

? MR enterography accurately detects mesenteric small bowel tumours. ? MR enterography is a well-tolerated imaging technique. ? Intravenous administration of gadolinium chelate improves sensitivity for detecting small-bowel tumours.     

Diagnostic accuracy of high-pitch dual-source CT for the assessment of coronary stenoses: first experience

Objectives

The objective was to prospectively investigate the diagnostic accuracy of high-pitch (HP) dual-source computed tomography coronary angiography (CTCA) compared with catheter coronary angiography (CCA) for the diagnosis of significant coronary stenoses.

Methods

Thirty-five patients (seven women; mean age 62?±?8 years) underwent both CTCA and CCA. CTCA was performed with a second-generation dual-source CT system permitting data acquisition at an HP of 3.4. Patients with heart rates >60 bpm were excluded from study enrolment. All coronary segments were evaluated by two blinded and independent observers with regard to image quality on a four-point scale (1: excellent to 4: non-diagnostic) and for the presence of significant coronary stenoses (defined as diameter narrowing exceeding 50%). CCA served as the standard of reference. Radiation dose values were calculated using the dose-length product.

Results

Diagnostic image quality was found in 99% of all segments (455/459). Non-diagnostic image quality occurred in a single patient with a sudden increase in heart rate immediately before and during CTCA. Taking segments with non-evaluative image quality as positive for disease, the sensitivity, specificity and positive and negative predictive values were 94, 96, 80 and 99% per segment and 100, 91, 88 and 100% per patient. The effective radiation dose was on average 0.9?±?0.1 mSv.

Conclusion

In patients with heart rates ≤60 bpm, CTCA using the HP mode of the dual-source CT system is associated with high diagnostic accuracy for the assessment of coronary artery stenoses at sub-milliSievert doses.     

Diagnostic performance of computed tomography coronary angiography to detect and exclude left main and/or three-vessel coronary artery disease

Objectives

To determine the diagnostic performance of CT coronary angiography (CTCA) in detecting and excluding left main (LM) and/or three-vessel CAD (“high-risk” CAD) in symptomatic patients and to compare its discriminatory value with the Duke risk score and calcium score.

Materials and methods

Between 2004 and 2011, a total of 1,159 symptomatic patients (61?±?11 years, 31 % women) with stable angina, without prior revascularisation underwent both invasive coronary angiography (ICA) and CTCA. All patients gave written informed consent for the additional CTCA. High-risk CAD was defined as LM and/or three-vessel obstructive CAD (≥50 % diameter stenosis).

Results

A total of 197 (17 %) patients had high-risk CAD as determined by ICA. The sensitivity, specificity, positive predictive value, negative predictive value, positive and negative likelihood ratios of CTCA were 95 % (95 % CI 91–97 %), 83 % (80–85 %), 53 % (48–58 %), 99 % (98–99 %), 5.47 and 0.06, respectively. CTCA provided incremental value (AUC 0.90, P?<?0.001) in the discrimination of high-risk CAD compared with the Duke risk score and calcium score.

Conclusions

CTCA accurately excludes high-risk CAD in symptomatic patients. The detection of high-risk CAD is suboptimal owing to the high percentage (47 %) of overestimation of high-risk CAD. CTCA provides incremental value in the discrimination of high-risk CAD compared with the Duke risk score and calcium score.

Key Points

? Computed tomography coronary angiography (CTCA) accurately excludes high-risk coronary artery disease. ? CTCA overestimates high-risk coronary artery disease in 47?%. ? CTCA discriminates high-risk CAD better than clinical evaluation and coronary calcification.     

Diagnostic accuracy of MDCT coronary angiography in patients referred for heart valve surgery

Purpose

The aim of our study was to evaluate the role of multidetector-row computed tomography (MDCT) in patients referred for heart valve surgery. We studied the diagnostic performance of CT coronary angiography (CTCA) compared with conventional coronary angiography (CCA) before valve surgery.

Materials and methods

During a 13-month period, 55 consecutive patients under evaluation for aortic (40/55) or mitral valve (15/55) disease before potential valve replacement underwent CTCA using a 64-detector-row scanner within 2 months of CCA for comparative purposes. All 17 major coronary artery segments were evaluated by one observer and compared with the reference standard. Patient-based, vessel-based and segment-based analyses of the data were performed.

Results

Prevalence of significant coronary artery disease, defined as having at least one stenosis ≥50% per patient, was 36%. On a patient-based analysis, sensitivity, specificity and positive and negative predictive values were 100%, 91%, 83% and 100%, respectively.

Conclusions

The diagnostic accuracy of 64-row CTCA for ruling out the presence of significant coronary stenoses in patients undergoing valve surgery is excellent and allows CTCA to be used as a gatekeeper for invasive CCA in these patients. MDCT is a necessary preoperative examination that provides useful information for identifying potential operative complications of surgical procedures.     

Acceptance of noninvasive computed tomography coronary angiography: for a patient-friendly medicine

Purpose

This study was done to evaluate the psychological state and anxiety of patients undergoing computed tomography coronary angiography (CTCA), and assess their acceptance and satisfaction compared to invasive conventional coronary angiography (CCA).

Materials and methods

A total of 442 consecutive patients (282 male; mean age 57.7 ± 9.5 years) who underwent CTCA for suspected or known coronary artery disease were evaluated with the Endler Multimodality Anxiety Scales (EMAS) before and after the scan, and a questionnaire administered after the scan. Among the 442 patients, 181 had a history of CCA. Two radiologists assessed the image quality of CTCA.

Results

Anxiety was more intense prior to the scan (EMAS score 51.7 vs. 46.7, p < 0.01) and in patients with a history of CCA (EMAS score 55.5 vs. 49.1, p < 0.01). Women presented more intense anxiety (EMAS score 59.5 vs. 47.3, p < 0.01), higher mean heart rate (63.5 ± 7.6 vs. 60.7 ± 7.3 beats per minute, p < 0.01) and a lower image quality than men (p < 0.0001). CTCA proved to be more acceptable than CCA because of accurate preparation, lower concern prior to the examination, negligible pain, higher comfort, and greater overall satisfaction (p < 0.0001).

Conclusions

Computed tomography coronary angiography is a patient-friendly imaging method because of the minimal perceived discomfort. Anxiety may affect CTCA image quality in women.     

Coronary artery disease: Which degree of coronary artery stenosis is indicative of ischemia?

Purpose

To prospectively determine the best cut-off value of stenosis degree for low-dose computed tomography coronary angiography (CTCA) to predict the hemodynamic significance of coronary artery stenoses compared to catheter angiography (CA) using a cardiac magnetic resonance based approach as standard of reference.

Materials and methods

Fifty-two patients (mean age, 64 ± 10 years) scheduled for CA underwent cardiac magnetic resonance (CMR) at 1.5-T and dual-source CTCA using prospective ECG-triggering the same day. Diagnostic performance of CTCA and CA to detect myocardial ischemia was evaluated with CMR as the standard of reference. The diagnostic performance and best cut-off values to predict the hemodynamic significance of coronary were determined from receiver operating characteristics analysis (ROC).

Results

CA revealed >50% stenoses in 131/832 segments (15.7%) in 78/156 (50.0%) coronary arteries in 32/52 (62%) patients. CTCA revealed >50% stenoses in 148/807 (18.3%) segments, corresponding to 83/156 (53.2%) coronary arteries in 34/52 (65.4%) patients. CMR revealed ischemia in 118/832 (14.2%) myocardial segments corresponding to the territories of 60/156 (38.5%) coronary arteries in 29/52 (56%) patients. ROC analysis showed equal diagnostic performance for low-dose CTCA and CA with areas under the curve (AUC) of 0.82 and 0.83 (P = 0.64). The optimal cut-off value was determined at stenosis of >60% for the prediction of hemodynamically significant coronary stenosis by CTCA. Using this cut-off value, sensitivity, specificity, NPV and PPV to predict hemodynamic significance by CTCA were 100%, 83%, 100%, and 88% on a per-patient basis and 88%, 73%, 83% and 81% on a per-artery analysis, respectively.

Conclusion

By considering coronary stenosis >60%, diagnostic performance for predicting the hemodynamic significance of coronary stenosis by CTCA is optimal and equals that of CA.     

Prognostic value of computed tomography coronary angiography in patients with chest pain of suspected cardiac origin

Purpose

The authors sought to determine the prognostic value of computed tomography coronary angiography (CTCA) in patients with acute chest pain (ACP).

Materials and methods

A total of 145 consecutive patients (75 men; 64??12 years) with ACP were referred from the Emergency Department for CTCA, which was performed with a standard protocol using a 64-slice scanner. Patients were stratified according to the Morise clinical score (low, intermediate, high) and to the CTCA findings [absence of coronary artery disease (CAD), nonobstructive CAD, obstructive CAD]. Patients were followed up for the occurrence of major events: cardiac death, nonfatal myocardial infarction, unstable angina and revascularisation.

Results

One hundred and twenty-seven (87.6%) patients were without a history of CAD, and 18 (12.4%) patients had a history of CAD. Obstructive CAD (>50% luminal narrowing) was detected in 35 (24%) patients; nonobstructive CAD (??50% luminal narrowing) in 62 (43%) and absence of CAD in 48 (33%) patients. During a mean follow-up of 20??3 months, 20 events occurred (four hard events). Sixteen events (three hard events) occurred in patients without a history of CAD, and four events (one hard event) occurred in patients with a history of CAD. In patients with absence of CAD as detected by CTCA, the rate of events was 0%. At multivariate analysis, hypercholesterolaemia and obstructive CAD were significant predictors of events (p<0.05).

Conclusions

An excellent prognosis was observed in patients with ACP and normal CTCA. CTCA shows the potential for optimal stratification of patients with ACP.     

Prognostic value of Morise clinical score, calcium score and computed tomography coronary angiography in patients with suspected or known coronary artery disease

Purpose

Our aim was to determine the prognostic value of computed tomography coronary angiography (CTCA), coronary artery calcium scoring (CACS) and Morise clinical score in patients with known or suspected coronary artery disease (CAD).

Materials and methods

A total of 722 patients (480 men; 62.7±10.9 years) who were referred for further cardiac evaluation underwent CACS and contrast-enhanced CTCA to evaluate the presence and severity of CAD. Of these, 511 (71%) patients were without previous history of CAD. Patients were stratified according to the Morise clinical score (low, intermediate, high), to CACS (0?C10, 11?C100, 101?C400, 401?C1,000, >1,000) and to CTCA (absence of CAD, nonsignificant CAD, obstructive CAD). Patients were followed up for the occurrence of major events: cardiac death, nonfatal myocardial infarction, unstable angina and revascularisation.

Results

Significant CAD (>50% luminal narrowing) was detected in 260 (36%) patients; nonsignificant CAD (<50% luminal narrowing) in 250 (35%) and absence of CAD in 212 (29%). During a mean follow-up of 20±4 months, 116 events (21 hard) occurred. In patients with normal coronary arteries on CTCA, the major event rate was 0% vs. 1.7% in patients with nonsignificant CAD and 7.3% in patients with significant CAD (p<0.0001). Three hard events (14%) occurred in patients with CACS??100 and two (9.5%) in patients with intermediate Morise score; one revascularisation was observed in a patient with low Morise score. At multivariate analysis, diabetes, obstructive CAD and CACS >1,000 were significant predictors of events (p<0.05).

Conclusions

An excellent prognosis was noted in patients with a normal CTCA (0% event rate). CACS ??100 and low-intermediate Morise score did not exclude the possibility of events at follow-up.