A case report on atypical angina: assessment of chest pain in primary care setting

Tak-kei Tse 謝德基，Catherine XR Chen 陳曉瑞

HK Pract 2022;44:59-63

Summary

摘要

Introduction

Chest pain is one of the most common presentations encountered in primary care and making a diagnosis can be challenging. Despite most cases of pain are noncardiac and benign in nature, it is the family physicians’ responsibility to pick up imminent cases of serious heart disease. Study found that 27.0% of patients with acute coronary syndrome (ACS) had visited the primary care in the preceding 30 days and up to 11.0% were missed and not referred for hospital care on those visits.⁴ In light of this, we report a case which presented with atypical chest pain in general practice and discussed the approach for proper assessment and identification of CAD in the primary care.

The Case

History

He described the chest pain as dull in nature, intermittent and lasted for 5 to 10 minutes each time. Every time, the pain was precipitated by lifting heavy weights at work and was relieved by rest. The chest pain did not occur when he walked upstairs or upslope. As his job was already labour-intensive, he did not have extra exercise. The last episode of chest pain was 5 days ago. Other than the pain, there was no nausea or vomiting, no sweating, no palpitation, no shortness of breath nor orthopnoea.

There was no history of injury to his body anywhere. To give further clarification of his shoulder pain, he revealed that he had suffered from shoulder pain since six months earlier and the pain had no temporal relationship with the onset of his present chest pain.

Physical examination

Musculoskeletal examination (MSK) found no obvious bony deformity. There was mild tenderness over both acromioclavicular joints with reduced range of movement on cross-body adduction.

Cardiac assessment was unremarkable, with no audible murmurs. There were no signs of heart failure with normal breathing sounds and no lower limb ankle oedema.

Investigation

Office electrocardiogram (ECG) (see Figure 1) was done and showed sinus rhythm with Q wave in V1 and T-wave inversion in II, III, aVF, V5-V6. There were no acute ST-segment changes.

Possibility of concomitant acromioclavicular osteoarthritis with stable angina was explained to the patient in view that the chest pain was associated with high level of exertion (i.e. lifting heavy objects), in addition, he had an abnormal baseline ECG and other cardiovascular risk factors including chronic smoker, obesity, sedentary lifestyle and comorbidities with T2DM and HT. The patient then proceeded with computerised tomography coronary angiography (CTA) with contrast in the private sector and the report showed 70% stenosis of right coronary artery (RCA), with 30% stenosis over proximal left anterior descending artery (LAD) and left circumflex artery (LCx). Aspirin and statin were started immediately, and he was referred to the cardiac team urgently for further management. At the same time, the patient was referred to the nurses for smoking cessation counselling, and diet and lifestyle modifications for body weight control.

Discussion

The first decision point for most physicians is whether the chest pain is caused by coronary ischemia. Clinical characteristics associated with an increased likelihood of ACS include male sex plus age over 60-years; diaphoresis; pain that radiates to the shoulder, neck, or jaw; and past history of angina or ACS.⁵ Our patient suffered from atypical chest pain which occurred only when he lifted heavy objects and was not aggravated by other physical activities. This history might indicate the pain to be MSK in origin. Indeed, studies have shown that most patients suspected of having CAD present with atypical or non-angina chest pain, only as few as 10-15% present with classic symptom of severe or crushing central chest pain exacerbated by exertion and relieved by rest.⁶

The differential diagnoses for chest pain are diverse.⁹ Although most common causes of chest pain in the primary care population include chest wall pain (20%), reflux esophagitis (13%) and costochondritis (13%)¹⁰, other life-threatening causes should not be missed (Table 1). One prospective cohort study identified four clinical factors that predict a final diagnosis of chest wall pain: localised muscle tension, stinging pain, pain reproducible by palpation, and the absence of a cough.¹¹ Burning retrosternal pain, acid regurgitation, sour or bitter taste in the mouth will support the diagnosis of gastroesophageal reflux disease.

     The initial goal in the management at outpatient setting is to determine whether the patient needs further testing such as troponin I or cardiac imaging test for ACS. The NICE guideline12 and ESC guideline6 have detailed algorithms on the assessment and diagnosis of recent onset chest pain of suspected cardiac origin. Firstly, we need to determine whether the patient is having acute chest pain or stable chest pain. Symptoms and signs that may indicate an ACS include (i) current chest pain lasting longer than 15 minutes, (ii) chest pain in past 12 hours with abnormal ECG, (iii) chest pain associated with nausea and vomiting, marked sweating, breathlessness, (iv) pain with haemodynamic instability, (v) new onset chest pain or abrupt deterioration in patients with known stable angina. These patients should be referred to the hospital or to cardiologist for urgent same-day assessment. As our case did not have symptoms suggestive of ACS and the last episode of chest pain occurred 5 days ago, it is reasonable to manage him in the outpatient setting.

For patients with suspected stable angina as with our case, detailed history and careful PE should be carried out to identify cardiovascular risk factors.¹³ Indeed, optimisation of cardiovascular risk factor modification is always an integral component of patient care in our daily practice. Our patient had multiple cardiovascular risk factors and therefore concerted effort should be made to ensure that all these are under good control.

Resting 12-lead ECG should be performed for the evaluation of all cases of chest pain, including atypical and non-anginal pain. Although normal resting ECG does not rule out stable angina, certain changes may indicate ischaemia or previous infraction. It includes pathological Q-waves, new onset left bundle branch block, ST-segment and T-wave abnormalities (flattening or inversion).¹⁴ In our case, the baseline ECG showed Q-wave and T-wave inversion. Although there was no previous ECG for comparison, these findings should prompt for further cardiac investigation.

Concerning the appropriate diagnostic tests for obstructive CAD, both functional and anatomical noninvasive tests can be considered.^6,12 Common functional tests include stress cardiac magnetic resonance and stress echocardiography. Anatomical non-invasive evaluation refers to CTA. In the latest update of NICE guideline in 2016¹², CTA is recommended as first line investigation for (i) typical or atypical angina or (ii) non-angina chest pain but resting 12-lead ECG indicates ST-T changes or Q-waves. To detect obstructive CAD at both thresholds of 50% and 70% stenoses, CTA can achieve sensitivity of 95-99%, specificity of 64-83% and a negative predictive value of 97-99%.^15,16 Furthermore, the 2019 the European Society of Cardiology (ESC) guideline⁶ also recommended the use of CTA as first line investigation for patients with a lower range of clinical likelihood of CAD. Significant CAD is defined as ≥70% diameter stenosis of at least one major epicardial artery segment or ≥50% diameter stenosis in the left main coronary artery. For our case, due to the limited resources and long waiting time for CTA in HAHK (more than 1 year), our patient had private CTA done and the report showed severe stenosis with ≥70% diameter stenosis over RCA with mild non-obstructing CAD over proximal LAD and LCx. Therefore, the case was referred to the cardiac team urgently for consideration of percutaneous coronary intervention.

     In the past, exercise ECG was recommended as one of the first line tests. Nowadays it has a limited role due to its inferior diagnostic performance to rule-in or rule-out obstructive CAD (sensitivity of 46-69% and specificity of 54-69%).¹⁷ Also, exercise ECG is not useful in patients with pre-existing ECG abnormalities (such as left bundle branch block, paced rhythm, Wolff- Parkinson-White syndrome, ≥0.1 mV ST-segment depression on resting ECG) that prevent interpretation of the ST-segment changes during stress, or in patients unfit for high-level exercise.⁶ However, it may still be considered as an alternative if other tests are not available.⁶ Therefore, family physicians should advise the pros and cons of different cardiac tests to patients thoroughly and the choice should be individualised according to patient’s risk and preference and the availability of the tests. A flow chart on chest pain assessment as modified from the NICE guideline¹² and ESC guideline⁶ is shown in Figure 2.

     For patients with stable angina, lifestyle modification and optimal medical therapy is the key for reducing symptoms, stopping progression of atherosclerosis, and preventing major adverse cardiovascular events. Revascularisation is always as an adjunct to medical therapy instead of replacing it⁶, but the indication and choice of revascularisation are beyond the scope of this article.

Referencess

1. Department of health, the Government of the Hong Kong Special Administrative Region. Health Facts of Hong Kong 2020 Edition. [Available from: https://www.dh.gov.hk/english/statistics/statistics_hs/files/2020.pdf.]
2. Centre for Health Protection, Deparment of Health, the Government of Hong Kong Special Administrative Region. Heart Diseases. Nov 2019 [Available from: https://www.chp.gov.hk/en/healthtopics/content/25/57.html.]
3. Census and Statistics Department, the Government of Hong Kong Special Administrative Region. Thematic Household Survey Report No. 68: Health Status of Hong Kong Residents. Nov 2019 [Available from: https://www.statistics.gov.hk/pub/B11302682019XXXXB0100.pdf.]
4. Sequist TD, Marshall R, Lampert S, et al. Missed opportunities in the primary care management of early acute ischemic heart disease. Arch Intern Med. 2006;166(20):2237-2243.
5. Rouan GW, Lee TH, Cook EF, et al. Clinical characteristics and outcome of acute myocardial infarction in patients with initially normal or nonspecific electrocardiograms (a report from the Multicenter Chest Pain Study). Am J Cardiol. 1989;64(18):1087-1092.
6. Knuuti J, Wijns W, Saraste A, et al. 2019 ESC Guidelines for the diagnosis and management of chronic coronary syndromes. Eur Heart J. 2020;41(3):407-477.
7. Hwang SY, Park EH, Shin ES, et al. Comparison of factors associated with atypical symptoms in younger and older patients with acute coronary syndromes. J Korean Med Sci. 2009;24(5):789-794.
8. Khafaji HA, Suwaidi JM. Atypical presentation of acute and chronic coronary artery disease in diabetics. World J Cardiol. 2014;6(8):802-813.
9. Murtagh J, Rosenblatt J, Coleman J, et al. Chest pain. John Murtagh's General Practice. 7th ed: McGraw-Hill Education (Australia) Pty Ltd; 2018.
10. Klinkman MS, Stevens D, Gorenflo DW. Episodes of care for chest pain: a preliminary report from MIRNET. Michigan Research Network. J Fam Pract. 1994;38(4):345-352.
11. Bosner S, Becker A, Hani MA, et al. Chest wall syndrome in primary care patients with chest pain: presentation, associated features and diagnosis. Fam Pract. 2010;27(4):363-369.
12. Excellence NIfHaC. Chest pain of recent onset: Assessment and diagnosis of recent onset chest pain or discomfort of suspected cardiac origin (update) [NICE guideline CG95]. 2016.
13. McConaghy JR, Oza RS. Outpatient diagnosis of acute chest pain in adults. Am Fam Physician. 2013;87(3):177-182.
14. Rude RE, Poole WK, Muller JE, et al. Electrocardiographic and clinical criteria for recognition of acute myocardial infarction based on analysis of 3,697 patients. Am J Cardiol. 1983;52(8):936-942.
15. Budoff MJ, Dowe D, Jollis JG, et al. Diagnostic performance of 64-multidetector row coronary computed tomographic angiography for evaluation of coronary artery stenosis in individuals without known coronary artery disease: results from the prospective multicenter ACCURACY (Assessment by Coronary Computed Tomographic Angiography of Individuals Undergoing Invasive Coronary Angiography) trial. J Am Coll Cardiol. 2008;52(21):1724-1732.
16. Meijboom WB, Meijs MF, Schuijf JD, et al. Diagnostic accuracy of 64-slice computed tomography coronary angiography: a prospective, multicenter, multivendor study. J Am Coll Cardiol. 2008;52(25):2135-2144.
17. Knuuti J, Ballo H, Juarez-Orozco LE, et al. The performance of non-invasive tests to rule-in and rule-out significant coronary artery stenosis in patients with stable angina: a meta-analysis focused on post-test disease probability. Eur Heart J. 2018;39(35):3322-3330.